Transcript
PHARMACOLOGY
Pharmacology
Study or science of drugs
3 Basic Areas of Pharmacology
Pharmaceutics
Pharmacokinetics
Pharmacodynamics
Pharmaceutics
Study of how various dosage forms (e.g., injection, capsule, controlled release tablet) influence the way in which the body metabolizes a drug and the way in which the drug affects the body
Pharmacokinetics
Study of what the body does to the drug molecules
Involves absorption, distribution, metabolism and excretion
Pharmacodynamics
Study of what the drug does to the body
Involves drug-receptor interactions
Receptor Theory
Pharmacotherapeutics
Focuses on the use of drugs and the clinical indications for administering drugs to prevent and treat diseases
Defines the principles of drug actions (the cellular processes that change in response to the presence of drug molecules)
Empirical therapeutics – drug therapy that is effective but for which the mechanism of action (MOA) is unknown
Rational therapeutics – drug therapy in which specific evidence has been obtained for the mechanisms of drug action
Toxicology
Study of the adverse effects of drugs and other chemicals on living systems
Toxic effects are often an extension of a drug’s therapeutic action
Pharmacognosy
Study of natural (vs synthetic) drug sources (both plants and animals)
PHARMACOKINETICS
Absorption
Distribution
Metabolism (biotransformation)
Excretion
A. Absorption
Rate at which and extent to which a drug moves from its site of administration
Factors affecting the rate and efficacy of absorption
Route of administration
Blood flow
Surface area available
Solubility of the drug
Drug interactions
pH (acidity (>uncharged) and alkalinity affects absorption)
Bioavailability
The fraction or biologic fluid of the administered drug that gains access to its site of action
IV injected blood – 100%
NOT IV injected - < 100%
Factors affecting Bioavailability
First pass metabolism – biotransformation that occurs before the drug reaches its site of action (MC site - liver)
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All of the factors affecting absorption: pH, blood flow, drug interactions, route of administration
Routes of Drug Administration
Alimentary (Oral, Buccal, Sublingual, Rectal/Suppository)
Parenteral (Intravenous, intramuscular, subcutaneous, intrathecal)
Inhalation
Topical
Subcutaneous
Routes of Administration
Sublingual
Under the tongue
Nitroglycerin
Oral
The drug is swallowed and absorbed through the stomach and intestinal tract
Oral Glucose
Aspirin
Inhalation
a gas or aerosol inhaled by the patient
Oxygen by mask
Albuterol by hand-held metered- dose inhaler or by small-volume nebulizer
Injection
The drug is injected into a muscle mass
Epinephrine by auto-injector
Medication Forms
Tablets
compressed powder shaped into a disk
Aspirin
Nitroglycerin
Liquid for Injections
liquid with no particulate matter
Epinephrine
Medication Forms
Gel
viscous substance that the patient swallows
Oral Glucose
Suspension
drug particles mixed in a solute
Activated Charcoal
Fine powder for Inhalation
a crystalline solid mixed with liquid to form a suspension
Albuterol by hand-held metered-dose inhaler
Gas
Oxygen by mask
Spray
Nitroglycerin sub-lingual spray
Liquid/vaporized
Albuterol by small-volume nebulizer
B. Distribution
Process by which a drug leaves the bloodstream and enters the interstitium or the cells of the tissues
Passive diffusion, transport o special carrier proteins, active transport
C. Metabolism/ Biotransformation
Involves the biochemical alteration of a drug into an inactive metabolite, a more soluble compound or a more potent active metabolite
Liver, (cytochrome P450 enzymes) skeletal muscle, kidneys, lungs, plasma and intestinal mucosa
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D. Excretion
Process by which a drug or metabolite is removed from the body
Renal (MC), fecal, respiratory, breast milk, skin
Half life
The time required for half of an administered dose of drug to be eliminated by the body
aka elimination half-life
Steady state
Physiologic state in which the amount of drug removed via elimination is equal to the amount of drug absorbed with each dose
Onset of action
Time required for the drug to elicit a therapeutic response
Peak effect
Time required for a drug toto reach its maximum therapeutic response
Duration of action
Length of time that the drug concentration is sufficient (without more doses) to elicit a therapeutic response
Peak level – highest blood level
Trough level – lowest drug level
Enzyme
Substance that catalyzes biochemical reactions in a cell
Agonist
A drug that binds to and stimulates the activity of one or more biochemical receptor types in the body
Antagonist
A drug that binds to and inhibits the activity of one or more more biochemical receptor types in the body
Theurapeutic index
Ratio of a drug’s toxic level to the level that provides therapeutic benefits
Drug interaction
Alteration of the action of one drug by another
Synergistic effects
Occur when two drugs administered together interact in such a way that their combined effects are greater than the sum of the effects for each drug given alone
Antagonistic effects
Occur when the combination of two drugs results in drug effects that are less than the sum of the effects for each drug given separately
Rights of Medication Use
Right patientRight drugRight timeRight routeRight doseRight documentationRight assessmentRight educationRight evaluation Right to refuse
Effects
The desired result of administration of a medication
Side Effects
Effects that are not desired and that occur in addition to the desired therapeutic effects
Medication error
A preventable situation in which there is a compromise in the five rights of medication use
Adverse Drug Reaction (ADR)
Any reaction to a drug that is unexpected and undesirable and occurs at therapeutic drug dosages
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Allergic Reaction
Aka as hypersensitivity reaction
An immune response wherein various chemical mediators (histamine, cytokines, other inflammatory substances) are released
Immunoglobulins recognize the drug, its metabolite or another ingredient in a drug formulation as a dangerous foreign substance; they bind to the substance in an attempt to neutralize it
Can result in mild reactions (skin erythema or rashes) or to severe/ life threatening reactions (constriction of bronchial airways and tachycardia)
Idiosyncratic reaction
Not the result of a known pharmacologic property of a drug or of a patient allergy but instead occurs unexpectedly in a particular patient
Genetically determined abnormal response to normal dosages of a drug (ex, deficiency or excess of an enzyme)
Teratogenic effects – result in structural defects in the fetus
Mutagenic effects – permanent changes in the genetic composition of living organis; consist of alterations in chromosome structure, the number of chromosomes, or the genetic code of the DNA
Carcinogenic effects – cancer-causing effects of drugs, other chemicals, radiation and viruses
Indication
The reason for administering a medication or performing a treatment
Contraindication
A factor that prevents the use of a medication or treatment (eg. Allergies)
Dose
The amount of a drug to be administered at one time
Mechanism of Action
How a drug works
Medication Names
Chemical Namedescribes the drug’s chemical structureGeneric Name reflects the chemical name, but in shorter formTrade Namethe name the manufacturer uses to market the drugOfficial Namethe name used in the U.S. Pharmocopoeia
Steps in Administering Medication
Obtain an OrderConfirm OrderSteps in Administering MedicationSelect Proper MedicationAvoid contaminationCheck Expiration DateCheck For Signs of ContaminationDiscolorationCloudinessParticulate MatterVerify Form & Route Inform Patient of OrderInquire about allergiesRecheck Medication Expiration dateContaminationAt least two more times after initial checkAssess Patient prior to administration of the drugAdminister the correct dose by the correct routeDispose of Contaminated EquipmentReassess After Administration
COMMONLY USED ABBREVIATIONS
a.c.ante cibumbefore mealsp.c.post cibumafter mealsad. lib.ad libitumas desiredodomni dieonce a daybidbis in dietwice a daytid
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ter in diethree times a dayqidquarter in dieFour times a dayADLActivities of daily livinghshora somnihours of sleepODoculus dexterright eyeOSoculus sinisterleft eyeOUoculus uterqueboth eyeso.m.omni maneevery morningn.p.o.nulla per oremnothing by mouthq.h.quaque horaevery hourp.r.n.pro re nataas necessarystatstatimimmediately Systems of Measurement Common Household Measurement
1 quart = 4 cups1 pint = 2 cups1 cup =8ounces1 tbsp =3 tsp; 15 mlL1 tsp =60 gtts;5mL
Apothecary Measurements60 minims = 1 fluidram8 fluidrams = 1 fluid ounce
or 480 minims16 fluid ounces = 1 pint2 pints = 1 quart4 quarts = 1 gallon
Metric MeasurementsUnits of volume (liter)
1 mL = .001 L
1 dL = .1 L1 decaliter = 10 Liters
Units of weight (gram)1 mcg = .000001 gm1 mg = .001 gm1 cg = .01 gm1 dg = .1 gm
1 kilogram = 1000 gramsOther units
1 gm. = 15 gr.1 gr = 60 mg1 mg = 1,000 mcg
1 mL = 1 cc; 15 gtts; 1 gram60 mcgtts
1 L = 1 qt; 1000 mL1 gal = 4 L; 4 qt., 4000 mL1 ounce = 30 gm., 30 cc1 kg = 2.2 lbs1 lb = 16 ounces
REVIEW OF THE AUTONOMIC NERVOUS SYSTEM Nervous System
1.Central Nervous System
2. Peripheral Nervous System
Peripheral Nervous System
1.Somatic Nervous System (innervates skeletal muscle)
2.Autonomic Nervous System (ANS) – collection of nuclei, cell bodies, nerves, ganglia, and plexuses that provides afferent and efferent innervation to smooth muscle and visceral organs of the body; regulates functions that are not under conscious control BP, HR and intestinal motility)
Autonomic Nervous System (ANS)
1.Sympathetic Nervous System- originates in the thoracolumbar portion of the spinal cord
2.Parasympathetic Nervous System – originates from the cranial nerve nuclei III, VII, IX, X as well as the 3rd and 4th sacral spinal roots
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Sympathetic Nervous System
Flight or fight situationsHR increasesBP risesEyes dilateBlood sugar / glucoses risesBronchioles expandBlood flow shifts from the skin to skeletal muscles
Sympathetic Nervous System Receptors:Adrenergic Receptors- alpha 1
alpha 2 beta 1
beta 2Dopamine Receptors
Parasympathetic Nervous System Rest and digest systemSlows HRLowers BPIncreases intestinal activityConstricts pupilsEmpties urinary bladder
Receptors:Cholinergic receptors – muscurinic
nicotinic Neurotransmitters Major NT in the ANSAcetylcholine – cholinergic transmissionNorepinephrine – adrenergic transmission ANS drugs achieve their effects by acting as either agonists or antagonists at cholinergic and adrenegic receptors
DRUGS Cardiovascular Drugs Positive Inotropic DrugsAntidysrhythmic DrugsAntianginal DrugsAntihypertensive DrugsAntilipemic Drugs
Coagulation Modifier Drugs AnticoagulantsAntiplatelet drugsAntifibrinolytic drugs
Thrombolytic Drugs Drugs Affecting the Renal System Diuretic Drugs
Endocrine Drugs Thyroid and Antithyroid DrugsAntidiabetic DrugsAdrenal Drugs
Drugs Affecting Reproductive Functions
Respiratory Drugs Antihistamines, Decongestants, Antitussives and ExpectorantsBronchodilators and others
Antiinfective Drugs AntibioticsAntiviral DrugsAntitubercular DrugsAntifungal DrugsOthers
Antiinflammatory and Antirheumatic Drugs
GIT Drugs Acid-controlling DrugsAntidiarrheals and laxativesAntiemetics and Antinausea DrugsVitamins and Minerals/ Nutrition Supplements
Drugs affecting the CNS Analgesic DrugsGeneral and Local AnestheticsCNS Depressants and Muscle RelaxantsAntiepileptic DrugsAntiparkinsonian DrugsPsychotherapeutic DrugsCNS Stimulants and Related Drugs
Drugs Affecting the Autonomic System Adrenergic DrugsAdrenergic-Blocking DrugsCholinergic DrugsCholinergic-Blocking Drugs
Immunosuppressant and Antineoplastic Drugs
OTHERS: Hematologic, Dermatologic, Ophthalmic and Otic Drugs
Cardiovascular DrugsDrugs used to improve CV function include: Inotropic drugs
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Antiarrhtymic drugsAntianginal drugsAntihypertensive drugsDiureticsAntilipemic drugsInotropic drugs
Influence the contractility of muscular tissue (increase the force of heart’s contarction) – POSITIVE INOTROPIC
2 types:1. cardiac glycosides- slow the heart rate (negative chronotropic effect)- slow electrical impulse conduction (negative dromotropic effect)2. phosphodiesterase (PDE)
Cardiac GlycosidesGroup of drugs derived from digitalis ( foxglove plants)Digoxin – most common prototype of cardiac glycosides
Pharmacokinetics:Capsules are absorbed most efficientlyFollowed by elixir then tabletsPoorly bound to plasma proteinsMost of the drugs is excreted by the kidneys unchanged
Pharmacodynamics:It boosts intracellular clacium at the cell membraneEnhance the movement of calcium into the myocardial cells and stimulate the release, or block the reuptake, of norepinephrine at the adrenergic nerve terminalActs on CNS
Pharmacotherapeutics:Heart failure, supraventricular arrhtymias, paroxysmal atrial tachycardia
Assessment:1. Obtain Hx 2. Monitor drug effectiveness – take apical
pulse for 1 minute before each dose3. Monitor digoxin levels (therapeutic blood
levels- 0.5 to 2 ng/ml)4. Obtain blood for digoxin levels 8 hours
after the last dose by mouth5. Closely monitor K levels Intervention:1. Before giving a loading dose, obtain a
baseline
2. Take the apical pulse before giving this meds
3. Wihthold the drug and notify the prescriber if the pulse rate slows to 60 bpm or less
4. Infuse the IV form slowly over at least 5 minutes
PDE InhibitorsTypically used for short term-term management of heart failure or long term management in patients awaiting heart transplant surgeryExamples:Inamrinone Milrinone
Warning:- when giving PDE inhibitors (milrinone), remember that improvement of cardiac output may result in enhanced UO. Expect a dosage reduction in diuretic therapy as heart failure improves- potassium loss may predispose the patient to
Digoxin toxicity
Antianginal Reducing myocardial oxygen demand (reducing the amount of oxygen the heart needs to do its work)Or by increasing the supply of oxygen to the heart
Three classes:Nitrates (acute angina)Beta-adrenergic blockers (long-term prevention of angina)Calcium channel blockers (used when other drugs fails)
Nitrates Commonly prescribed:Amyl nitriteIsosorbide dinitrateIsosorbide mononitrateNitroglycerin
Assessment:Monitor VS – IV nitroglycerin (monitor BP and PR q 5 to 15 minutes while adjusting the dose and every hour thereafter)Monitor the effectiveness of prescribed drugsObserve for adverse reactions
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Interventions:Maybe given on empty stomach, either 30 minutes before or 1 to 2 hours after meals (tell to swallow not chew)Have the patient sit or lie down when receiving the first nitrate dose (take pulse/BP before giving the dose)Don’t give beta-adrenergic blocker or calciul channel blocker to relieve anginaWihthold if heart rate < 60bpmDilute IV nitro with D5W or NSS for injection (avoid IV filters because it binds to plasticSublingual nitro can be repeated every 10 to 15 minutes up to 3 dosePlace topical ointments on paper as prescribed; place the paper on a nonhairy area and cover it with plasticRemove a transdermal patch before defibrillation (aluminum back may be explode)Be aware that the drug may initially cause headache until tolerance develops or the dose is minimized
Antihypertensive drugsUsed to treat hypertensionClasses:Angiotensin-converting enzyme (ACE) inhibitorsAngiotensin-receptor blockersBeta-adrenergic antagonistCalcium channel blockerDiuretics
ACE inhibitorReduce BP by interrupting the renin-angiotensin activating system (RAAS)Commonly used:CaptoprilEnalaprilLisinoprilRamiprilAssessment:Obtain a baseline BP and pulse rate and rhythmMonitor adverse reactions (headache, fatigue, dry non-productive cough, angioedema, tickling in the throat)Monitor monitor weight, fluid and electrolyte statusMonitor a transdermal patch for dermatitisIntervention:If orally, administer before mealsAssist the patient to get up slowly to prevent orthostatic hypotensionSodium restriction, calorie reduction, stress mngt, exercise program should be maintainPeriodic eye examinations are recommended
Angiotensin II receptor blocking agents Lower BP by blocking the vasoconstrictive effects of angiotension IICommonly used:LosartanValsartanIrbesartantelmisartan Assessment:Obtain baseline VSWeight, fluid and electrolytes statusCompliance and treatmentTolerance and therapeutic effectsDermatitisAdverse reactionsInterventions:If orally administer the drug with food or at bedtimeIf giving once daily, administer in the morning to prevent insomia
Beta-adrenergic blockersAlso used for long term prevention of anginaCommonly used:AtenololBisoprololCarvedilolNadololPindolol
Calcium channel blockersAlso used to treat arrhythmias and to prevent anginaCommonly used:Amlodipine Nifedipine verapamil
Sympatholytic drugsReduce blood pressure by inhibiting or blocking the SNSClassified by their site or mechanism of action and include:Central-acting SNS inhibitors – clonidine Hcl, methyldopaAlpha adrenergic blockers – prazosin, terazosin Mixed alpha and beta-adrenergic blockers – carvedilol, labetalol Norepinephrine depletors – reserpine
Direct vasodilatorsDecrease systolic and diastolic BPThey act on arteries, veins or both
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Examples:Diaxozide Hydralazine Nitroprusside
Renal PharmacologyDrugs affecting the KidneyOutline of reviewRecall the anatomy of the urinary systemRecall the physiology of the urinary systemReview- drugs of the following categories:1. Diuretics2. Drug for BPH
DiureticsAgents that increase the amount of urine produced by the kidneys
Classes of DiureticsFive major classes1. Thiazides and thiazide-like2. Loop diuretics3. Potassium-sparing 4. Carbonic anhydrase inhibitors5. Osmotic diuretics
General indications for the use of the diureticsTreatment of edemaUrine output will increase and excess fluid is flushed out of the body
Treatment of CHFThe sodium loss in the kidney is associated with water loss
Treatment of HypertensionDiuretics will decrease the blood volume and serum sodium
Treatment of GlaucomaDiuretics will provide osmotic pull to remove some of the fluid from the eye to decrease the IOP
time of administration of the diureticsUsually in the morning!!
Diuretics ComparisonThiazidesPrototype: Hydrochlorothiazide 1. Bendroflumethiazide 2. Benthiazide 3. Chlorothiazide (Diuril)4. Hydroflumethiazide 5. Methylclothiazide
6. Trichlormethiazide
Thiazide-like1. Indapamide2. Quinethazone3. Metolazone4. Chlorthalidone
ThiazidesPharmacodynamicsThese drugs BLOCK the chloride pumpThis will keep the Chloride and Sodium in the distal tubule to be excreted into the urine Potassium is also flushed out!!
Special Pharmacodynamics: Side effectsHypokalemiaDECREASED calcium excretionà hypercalcemiaDECREASED uric acid secretionà hyperuricemiaHyperglycemia
Loop DiureticsPrototype: Furosemide 1. Bumetanide 2. Ethacrynic acid3. Torsemide
Pharmacodynamics High-ceiling diureticsBLOCK the chloride pump in the ascending loop of Henle SODIUM and CHLORIDE reabsorption is preventedPotassium is also excreted together with Na and Cl
Special Pharmacodynamics: side-effectsHypokalemiaBicarbonate is lost in the urineINCREASED calcium excretionà HypocalcemiaOtotoxicity- due to the electrolyte imbalances
Potassium sparing diureticsPrototype: Spironolactone 1. Amiloride 2. Triamterene
Potassium sparing diureticsPharmacodynamics Spironolactone is an ALDOSTERONE antagonistTriamterene and Amiloride BLOCK the potassium secretion in the distal tubuleDiuretic effect is achieved by the sodium loss to offset potassium retention
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Potassium sparing diureticsPharmacokinetics: Side effectsHYPERkalemia!Avoid high potassium foods:BananasPotatoesSpinachBroccoliNutsPrunesTomatoesOrangesPeaches
Osmotic DiureticsPrototype: Mannitol 1. Glycerin2. Isosorbide 3. Urea
Osmotic DiureticsPharmacodynamicsMannitol is a sugar not well absorbed in the nephronà osmotic pull of waterà diuresis
Pharmacokinetics: side effectsSudden hypovolemia Important for the nurse to warm the solution to allow the crystals to DISSOLVE in the bottle!
Carbonic Anhydrase InhibitorsPrototype: Acetazolamide 1. Methazolamide Carbonic Anhydrase InhibitorsPharmacodynamicsCarbonic Anhydrase forms sodium bicarbonateBLOCK of the enzyme results to slow movement of hydrogen and bicarbonate into the tubulesplus sodium is lost in the urinePharmacokinetics: side effectsMetabolic ACIDOSIS happens when bicarbonate is lostHypokalemia
The Nursing Process and the diureticsASSESSMENTAssess the REASON why the drug is given:ASSESSMENTThe nurse must elicit history of allergy to the drugs
Allergy to sulfonamides may contraindicate the use of thiazides Assess fluid and electrolyte balanceAssess other conditions like gout, diabetes, pregnancy and lactation
ASSESSMENTPhysical assessmentVital signsSpecial electrolyte and laboratory examinationAssess symptom of body weakness which may indicate hypokalemia
Nursing DiagnosisFluid volume deficit related to diuretic effectAlteration in urinary patternPotential for injury (ototoxocity, hypotension)Knowledge deficit
IMPLEMENTATIONAdminister IV drug slowlySafety precaution for dizziness/hypotensionProvide potassium RICH foods for most diuretics, with the exception of spironolactone Provide skin care, oral care and urinary care
IMPLEMENTATIONMonitor DAILY WEIGHT- to evaluate the effectiveness of the therapy Monitor urine output, cardiac rhythm. Serum electrolytesADMINISTER in the MORNING!Administer with FOOD!
EVALUATION: for effectiveness of therapyWeight lossIncreased urine outputResolution of edemaDecreased congestionNormal BP
Pharmacology of the Selected Endocrine DrugsEndocrine MedicationsThyroid Medications
Thyroid hormonesThese products are used to treat the manifestations of hypothyroidismReplace hormonal deficit in the treatment of
HYPOTHYROIDSMFatigueWeight gainCold intolerance
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Irregular MensesMyxedema
ANTI-THYROID medications1. Methimazole (Tapazole)2. PTU (prophylthiouracil)3. Iodine solution- SSKI and Lugol’s solution
ANTI-THYROID medications: Indications (hyperthyroidism)
1. Grave’s disease 2. Thyrotoxicosis
Hyperthyroidism Hypersensitivity to heatWeight loss despite increased appetiteNervousness (palpitation)Sweating
ANTI-THYROID medications:Absorption is good orally
Side-effects of thionamides N/V, drowsiness, lethargy, bradycardia, skin rashGI complaintsArthralgia, myalgia AGRANULOCYTOSISMost important to monitor
Side-effects of Iodine solutions Lugol’sMost common adverse effects is HYPOTHYROIDISMIodism= metallic taste, burning in the mouth, sore teeth and gums, diarrhea, stomach upset
Nursing responsibilities1. Monitor VS, T3 and T4, weight2. The medications WITH MEALS to avoid gastric upset3. Instruct to report SORE THROAT or unexplained FEVER4. Monitor for signs of hypothyroidism. Instruct not to stop abrupt medicationLugol’s SolutionUsed to decrease the vascularity and size of the thyroid (in preparation for thyroid surgery) T3 and T4 production diminishesGiven per orem, can be diluted with juice, administered WITH foodsUse straw to decrease stainingMonitor iodism
Thyroid Storm Surgery, stress or illness
Endocrine MedicationsAnti-diuretic hormonesEnhance re-absorption of water in the kidneysIncreases water permeability in the renal collecting ductsAlso stimulates VASOCONSTRICTION and increases the blood pressure
Therapeutic Indications1. Hormonal replacement2. Used in diagnostic procedure3. Used to control the hemorrhage in
variceal bleeding 4. Treatment of enuresis
Used in DI1. Desmopressin and Lypressin intranasally2. Pitressin IntraMuscularlyEndocrine MedicationsAnti-diuretic hormones
SIDE-effectsFlushing and headacheWater intoxicationCVS: heart block, MIRenal: hyponatremiaGangrene due to vasoconstriction DM Drug therapy
DRUG THERAPY and MANAGEMENTUsually, this type of management is employed if diet modification and exercise cannot control the blood glucose level.
These agents are employed to control the blood glucose levelThey can be insulin and oral agentsThese are given to replace the hormone in the bodyIf hormone is still present BUT decreased, Oral agents are given
Diabetes MellitusDRUG THERAPY and MANAGEMENTBecause the patient with TYPE 1 DM cannot produce insulin, exogenous insulin must be administered for life.
TYPE 2 DM may have decreased insulin production, ORAL agents that stimulate insulin production are usually employed.
PHARMACOLOGIC INSULIN
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This may be grouped into several categories according to:
1. Source- Human, pig, or cow2. Onset of action- Rapid-acting, short-
acting, intermediate-acting, long-acting and very long acting
PHARMACOLOGIC INSULINThis may be grouped into several categories according to:
3. Pure or mixed concentration4. Manufacturer of drug
Diabetes MellitusGENERALITIES1. Human insulin preparations have a shorter duration of action than animal sourceDiabetes Mellitus2. Animal sources of insulin have animal proteins that may trigger allergic reaction and they may stimulate antibody production that may bind the insulin, slowing the action 3. ONLY Regular insulin can be used INTRAVENOUSLY!Diabetes Mellitus4. Insulin are measured in INTERNATIONAL UNITS or “iu”5. There is a specified insulin injection calibrated in unitsMixed insulin are also availableThe most common of which is the 70-30 insulinMade up of :70% NPH and 30% regular insulin in the vial
Comparison of Insulin Peak actionDiabetes MellitusRAPID ACTING INSULINLispro (Humalog) and Insulin Aspart (Novolog)Produces a more rapid effect and with a shorter duration than any other insulin preparation
RAPID ACTING INSULINONSET- 5-15 minutesPEAK- 1 hourDURATION- 3 hoursInstruct patient to eat within 5 to 15 minutes after injection
REGULAR INSULINAlso called Short-acting insulin“R”Usually Clear solution administered 30 minutes before a mealDiabetes Mellitus
REGULAR INSULINONSET- 30 minutes to 1 hourPEAK- 2 to 4 hoursDURATION- 4 to 6 hours
INTERMEDIATE ACTING INSULINCalled “NPH” or “LENTE”Appears white and cloudy
INTERMEDIATE ACTING INSULINONSET- 2-4 hoursPEAK- 4 to 6-12 hoursDURATION- 16-20 hours
LONG- ACTING INSULIN“UltraLENTE”Referred to as “peakless” insulinLONG- ACTING INSULINONSET- 6-8 hoursPEAK- 12-16 hoursDURATION- 20-30 hours
HEALTH TEACHINGRegarding Insulin SELF- Administration1. Insulin is administered at home subcutaneouslyDiabetes Mellitus2. Cloudy insulin should be thoroughly mixed by gently inverting the vial or ROLLING between the hands3. Insulin NOT IN USE should be stored in the refrigerator, BUT avoid freezing/extreme temperature4. Insulin IN USE should be kept at room temperature to reduce local irritation at the injection site5. INSULIN may be kept at room temperature up to 1 month6. Select syringes that match the insulin concentration.U-100 means 100 units per mL7. Instruct the client to draw up the REGULAR (clear) Insulin FIRST before drawing the intermediate acting (cloudy) insulin8. Pre-filled syringes can be prepared and should be kept in the refrigerator with the needle in the UPRIGHT position to avoid clogging the needle9. The four main areas for insulin injection are- ABDOMEN, UPPER ARMS, THIGHS and HIPSInsulin is absorbed fastest in the abdomen and slowest in the hipsInstruct the client to rotate the areas of injection, but exhaust all available sites in one area first before moving into another area.10. Alcohol may not be used to cleanse the skin
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11. Utilize the subcutaneous injection technique- commonly, a 45-90 degree angle. 12. No need to instruct for aspirating the needle13. Properly discard the syringe after use.
T-I-ETest bloodà Inject insulin à Eat food
ORAL HYPOGLYCEMIC AGENTSThese may be effective when used in TYPE 2 DM that cannot be treated with diet and exerciseThese are NEVER used in pregnancy!
ORAL HYPOGLYCEMIC AGENTSThere are several agents:SulfonylureasBiguanidesAlpha-glucosidase inhibitorsThiazolidinedionesMeglitinides
These drugs are given per orem and are effective only in type 2 DMCommon adverse effects include:HypoglycemiaDiarrhea, jaundice, nausea and heartburnAnemia , photosensitivity
General Nursing Consideration1. Observe for manifestations of
hypoglycemia2. Assess for allergic reaction3. Instruct to take the medication at the
same time each day4. Caution to avoid taking other drugs
without consultation with physician5. THESE medications SHOULD NEVER be given to pregnant women, so rule out pregnancy6. Instruct to wear sunscreen7. Advise to bring simple sugar to be taken when hypoglycemic episodes occur
SULFONYLUREASMOA- stimulates the beta cells of the pancreas to secrete insulinClassified as to generations- first and second generations
FIRST GENERATION- Acetoheximide, Chlorpropamide, Tolazamide and TolbutamideSECOND GENERATION- Glipizide, Glyburide, Glibenclamide, GlimepirideDiabetes Mellitus: Sulfonylureas
The most common side –effects of these medications are Gastro-intestinal upset and dermatologic reactions.HYPOGLYCEMIA is also a very important side-effectGiven 30 minutes before meals- breakfast
Diabetes Mellitus: SulfonylureasChlorpropamide has a very long duration of action. This also produces a disulfiram-like reaction when taken with alcoholSecond generation drugs have shorter duration with metabolism in the kidney and liver and are the choice for elderly patients
BIGUANIDESMOA- Facilitate the action of insulin on the peripheral receptorsThese can only be used in the presence of insulin
BIGUANIDES= “formin”They have no effect on the beta cells of the pancreas Metformin (Glucophage) and Phenformin are examplesThe most important side effect is LACTIC ACIDOSIS!These are not given to patient with renal impairmentThese drugs are usually given with a sulfonylurea to enhance the glucose-lowering effect more than the use of each drug individually
ALPHA-GLUCOSIDASE INHIBITORSMOA- Delay the absorption of glucose in the GIT Result is a lower post-prandial blood glucose levelThey do not affect insulin secretion or action!Side-effect: DIARRHEA and FLATULENCEExamples of AGI are Acarbose and MiglitolThey are not absorbed systemically and are very safeThey can be used alone or in combination with other OHASide-effect if used with other drug is HYPOGLYCEMIANote that sucrose absorption is impaired and IV glucose is the therapy for the hypoglycemia
THIAZOLIDINEDIONESMOA- Enhance insulin action at the receptor siteThey do not stimulate insulin secretionExamples- Rosiglitazone, PioglitazoneThese drugs affect LIVER FUNCTION
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Can cause resumption of OVULATION in peri-menopausal anovulatory women
MEGLITINIDESMOA- Stimulate the secretion of insulin by the beta cellsExamples- Repaglinide and NateglinideDiabetes Mellitus
MEGLITINIDESThey have a shorter duration and fast actionShould be taken BEFORE meals to stimulate the release of insulin from the pancreasDiabetes MellitusMEGLITINIDESPrincipal side-effect of meglitinides- hypoglycemiaCan be used alone or in combinationReproductive HormonesGonadal hormones include agents that affect the female and male reproductive cycleFemale hormones include ESTROGENS, PROGESTINS and ovarian hormonesMale hormones include ANDROGENS and anabolic steroidsReproductive HormonesThe GENERAL Mechanism of ActionThese hormones interfere with the normal cycle of hormone balanceReproductive HormonesINDICATIONS
1. FEMALE: Hormonal replacement therapy, oral contraception, treatment of infertility and management of some tumors
2. MALE: replacement therapy, metabolic stimulators and treatment of some tumors
Reproductive HormonesEstrogensConjugated estrogenEstradiolEthinyl estradiolDiethylstilbesterol (DES)ClomipheneReproductive HormonesProgestinsMedroxyprogesterone acetate (Provera)MegestrolNorethindroneLevonorgestrel (Norplant)NorgestrelNorethindrone acetateReproductive HormonesAndrogensTestosterone cypionate
MethyltestosteroneFluoxymesteroneAqueous testosteroneReproductive HormonesOral Contraceptive PillsTwo types are available: Combination estrogen and progesterone AND progestins onlyReproductive HormonesOral Contraceptive Pills: DYNAMICSInhibits OVULATION by altering the hypothalamus and gonadotropin axisAlters the MUCUS to prevent sperm entryAlters the uterine endometrium to prevent implantation Suppresses the ovariesReproductive HormonesOral Contraceptive Pills: IndicatorsSuppression of ovulation for prevention of pregnancyRegulation of menstrual cycle and management of dysfunctional bleeding Treatment of endometriosisReproductive HormonesOral Contraceptive Pills: KineticsEasily absorbed orallyNORPLANT provides 5 years of contraception Provera provides 3 months of protectionMetabolized and excreted in liverReproductive HormonesOral Contraceptive Pills:Not to be used in patients with history of, hypertension, thromboemoblic or CVA diseaseNot given in certain cancersContraindicated in pregnancySMOKING should be avoided when under therapyReproductive HormonesOral Contraceptive Pills: Drug InteractionRifampicin, penicillin and tetracycline REDUCE effectiveness of contraceptionBenzodiazepines decrease the levels of OCP Reproductive HormonesOral Contraceptive Pills:Side effectsCNS: headacheCV: Thromboembolic disease, MI, hypertension and pulmonary edemaNAUSEA and cholestatic JAUNDICEBreast tenderness, weight gain, edema, breakthrough bleeding, acne Reproductive hormonesNursing Considerations
1. Assess for risk factors and the ability to comply with medications
2. Determine the type of OCP used
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Monophasic pills provide constant dosing of BOTH estrogen and progestinBiphasic pills provide constant estrogen but varying progestin dosesTriphasic pills provide varying Estrogen and ProgesteroneReproductive hormonesNursing Considerations3. Teach the common side-effects and re-assure that these will decrease in time4. Instruct to use other means of contraception if antibiotics and anticonvulsants are also taken5. WARN the client to avoid smoking because this will increase the risk for embolic episodes ClomipheneA synthetic, non-steroidal estrogen Increases the secretion of gonadotropins and initiates the secretion of FSH and LHOVULATION will occurUsed in the treatment of infertilityReadily absorbed orally ClomipheneSide effects can be:Risk for Multiple pregnancyNausea, breast discomfort, headache and GI disturbancesVisual disturbancesEnlargement of the ovariesViagra (Sildenafil)A medication used for penile erectile dysfunctionSelectively inhibits receptors and enzyme Phosphodiesterase EThis increases the nitrous oxide levels allowing blood flow into the corpus cavernosum Viagra (Sildenafil)Contraindicated in patients with bleeding disorders and with penile implantsCaution: Coronary Artery Disease and concomitant use of nitratesSide-effects: PRIAPISM, headache, flushing, dyspepsia, UTI, diarrhea and dizziness Viagra (Sildenafil)Nursing considerationAssess for risk factorsInstruct to take the drug ONE hour before sexual actDrug is taken orallyPharmacology of Respiratory DrugsDrugs Affecting the Respiratory SystemAntihistamines- are used to block the release or action of histamine- a chemical mediator of inflammation that increases secretions and constricts the air passageway
Antitussives- agents utilized to block the cough reflexDrugs for COPD (chronic obstructive pulmonary disease)- which includes the Bronchodilators, inhaled steroids, Leukotriene receptor blockers and other anti-asthma drugsDecongestants- are utilized to decrease the blood flow to the upper respiratory tract and decrease the excessive production of secretionsExpectorants- are used to decrease the viscosity of sputum to effectively increase productive cough to clear the airwaysThe ANTIHISTAMINESAlso called H1 blockers or H1 antagonists, these are agents designed to relieve respiratory symptoms and to treat allergic conditions.The ANTIHISTAMINESThe anti-histamines are group according to the “generation”. The FIRST GENERATION agents have greater anticholinergic effects and can cause more sedation and drowsiness! These agents cause drowsiness. The SECOND GENERATION agents have fewer anticholinergic effects that is why they cause less sedation. The ANTIHISTAMINESThe FIRST GENERATION ANTIHISTAMINES1. Azatadine 11. Dimenhydrinate 2. Azelastine 12. Diphenhydramine 3. Brompheniramine 13. Hydroxyzine 4. Buclizine 14. Meclizine 5. Cetirizine 15. Methdilazine 6. Chlorpheniramine 16. Promethazine 7. Clemastine 17. Tripelenamine 8. Cyclizine 18. Carbinoxamine9. Cyproheptadine 19. Trimeprazine 10. Dexchlorpheniramine 20. Triprolidine The ANTIHISTAMINESThe SECOND GENERATION ANTIHISTAMINESFexofenadineLoratidineAzelastineCetirizineAnti-HistamineThe Mechanism of Action
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These agents SELECTIVELY block the effects of histamine at the HISTAMINE-1 receptor sites in the target tissue by competing with histamine for receptor, decreasing the cellular responses They also have antipruritic property.Anti-HistamineClinical Indications for Use in respiratory system
1. rhinitis2. allergic sinusitis3. uncomplicated urticaria
Anti-HistamineContraindications and Precautions for the use of the antihistaminesPregnancy and lactation are contraindications, and they agents are used cautiously in patient with impaired liver and kidney functions. Fatal arrhythmiasAnti-HistaminePharmacodynamics: Drug effects on the body
1. CNS- drowsiness and sedation, most pronounced if first generation agents are used
2. Fatigue, dizziness and disturbed coordination.
3. Anticholinergic effects= drying of the respiratory mucus membrane, GI upset and nausea, arrhythmias, dysuria, urinary retention
4. Skin dryness Anti-HistamineImplementationThe nurse should administer the drug on an EMPTY stomach, or 1 hour before or 2 hours after meals to increase the absorption. Give with food if GI upset occurs Offer sugarless lozenges or hard candy to counteract dryness of the mouth. Give frequent oral careProvide safety measures if drowsiness may occur. Side rails up, assist in ambulation, and advise not to drive or operate dangerous machineries or delicate tasks. Anti-HistamineNursing implementationIncrease humidity in the room by utilizing nebulizers and provide adequate hydrationAllow the patient to void first before administering the drug. Caution the patient against use of OTC drugs, alcoholic beverages and sedatives because they may cause extreme sedation.Anti-HistamineEvaluation
Monitor patient’s response to the drug, the adverse effects and the effectiveness of comfort measures employedDecreased allergic symptomsDecreased occurrence of rhinitisAnti tussivesThese are agents suppress the cough reflex on the MEDULLA oblongata to suppress cough of many respiratory conditions. The anti-tussives are the following:Benzonatate= narcotic anti-tussiveButamirate citrate= non-narcoticCodeine= narcoticDextromethorphan= non-narcoticHydrocodone= narcoticAnti tussivesPharmacodynamics: Therapeutic use of the antitussivesThe traditional antitussives act directly on the MEDULLARY cough of the brain to depress the cough reflex, but it does NOT suppress respiration.Dextromethorphan DOES not depress respiration. AntitussivesClinical Use of the antitussive: utilized for the treatment of coughContraindications and Indications for use of antitussivesThese agents are NOT given to patients who have undergone thoracic surgeries because they need to cough to maintain airway patency. Precautions are instituted when giving to patients with asthma, emphysema or COPD because an accumulation of secretions may occur. Anti tussives
Pharmacodynamics: Drug Effects
Respiratory- dryness of mucosal membranes, increased viscosity of secretions
CNS- drowsiness, dizziness and sedation
GIT- nausea, constipation and dry mouth, GIT upset
Nursing Process and the antitussives
Anti tussives
Implementation
Emphasize that the drug should be taken only on a specified time frame as ordered
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Provide other measures to relieve cough like provide humidified oxygen, cool temperatures, fluids and use of lozenges
Provide health teaching as to drug name, dosage and measures to handle side-effects
Caution that alcohol, narcotics, sedatives-hypnotics can cause CNS depression when used with antitussives.
Mucolytics
These are agents that breakdown mucous in order to help respiratory patients in coughing up thick, tenacious secretions.
The following are the mucolytics:
Acetylcysteine
Dornase alfa
Mucolytics
Pharmacodynamics: Mechanism of Action
These agents work in the following ways: acetylcysteine affects the mucoproteins in the respiratory secretions by splitting apart disulfide bonds that are responsible for holding the mucus materials together.
Mucolytics
Cautions should be used in cases of acute bronchospasms, peptic ulcer and esophageal varices.
The increased secretions can aggravate the problem
Indications for use
COPD
Pneumonia
Tuberculosis
Atelectasis
Mucolytics
Pharmacodynamics: drug effects
GIT= GI upset, stomatitis, irritation of the respiratory tract
others: Bronchospasm and rash
Mucolytics
Implementation
Instruct the patient to avoid combining with other drugs in the nebulizer to avoid formation of precipitates
The dug can be administered via nebulizers with the drug diluted with sterile water.
Remind the patient that the drug may irritate the respiratory mucosa
Provide through patient teaching including drug name and prescribed dosage
Have suction machine available
Drugs for COPD
The agents used for COPD may be one of the following:
Bronchodilators such as adrenergics and the xanthines used to assist in opening the narrowed airways
Steroids are used to decrease inflammation
Leukotriene modifiers reduce inflammation in the lung tissue
Cromolyn sodium and nedocromil act as anti-inflammatory agents by suppressing the release of HISTAMINE from the mast cells
Expectorants are used to assist in loosening secretions from the airways
Antibiotics are prescribed to prevent serious complications from bacterial infections.
The BRONCHODILATORS
These are Bronchodilators medication used to facilitate respiration by dilating the airways.
They are helpful in symptomatic relief or prevention of bronchial asthma and bronchospasm associated with COPD.
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The BRONCHODILATORS
The bronchodilators are:
Xanthines
Sympathomimetics (beta-agonists)
Anticholinergics
Inhaled steroids
The XANTHINES
Xanthines, including caffeine and theophylline, come from a variety of naturally occurring sources. These drugs were once main choice for treatment of asthma and bronchospasm.
The Xanthines include:
Aminophyline
Caffeine
Dyphilline
Oxytriphylline
Pentoxyfilline
Theophylline
The XANTHINES
Pharmacodynamics: Drug action
The xanthines have a direct effect on the smooth – muscles of the respiratory tract, both those on the bronchi and the blood vessels.
The xanthines stimulate the CNS such that respiration is stimulated, coronary arteries dilate and pulmonary arteries dilate, with additional effect of diuresis.
The XANTHINES
Clinical Use of the xanthines
Xanthines are indicated for the symptomatic relief or prevention of bronchial asthma and reversal of bronchospasm associated with COPD.
Unlabeled uses include stimulation of respiration in Cheyne – Stokes respiration and
the treatment of apnea and bradycardia in premature infants.
The XANTHINES
Pharmacodynamics: drug effects
GI upset, anorexia, vomiting, gastric pain, nausea, irritability, and tachycardia to seizures, brain damage, and even death.
Theophylline toxicity occurs when concentration is above 20 ug/mL.
Rapid IV administration of aminophylline can cause dizziness, flushing, severe HYPOTENSION, bradycardia and palpitations.
The XANTHINES
Implementation
Monitor vital signs and note for the BP and HR because there may be Hypotension and tachycardia.
Administer oral drug with food to relieve GI irritation, if GI upset is a problem.
Monitor patient response to the drug= relief of respiratory difficulty and improved airflow, to determine the effectiveness of the drug dosage and to adjust dosage as needed.
The XANTHINES
Implementation
Provide comfort measures, including rest periods, quiet environment, dietary control of caffeine, and headache therapy as needed, to help the patient cope with the effects of drug therapy.
Provide adequate hydration
Don’t crush enteric coated and sustained release tablets
Encourage to stop smoking
The XANTHINES
Evaluation
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Monitor patient response to the drug (improved air flow, ease of respirations).
Monitor for adverse effects (CNS effects, cardiac arrhythmias, GI upset, local irritation)
The SYMPATHOMIMETICS
These are drugs that mimic the effects of the sympathetic nervous system.
One of the actions of the sympathetic nervous system is dilation of the bronchi and increased rate and depth of respiration.
This is the desired effect when selecting a sympathomimetic as a bronchodilator.
The SYMPATHOMIMETICS
Sympathomimetics that are used as bronchodilators include the following:
Albuterol
Bitolterol
Isoproterenol
Metaproterenol
Salbutamol
Terbutaline
Ephedrine
Epinephrine= the drug of choice for the treatment of acute bronchospasm, including that which is caused by anaphylaxis
The SYMPATHOMIMETICS
Clinical Use
Asthma and other Allergic conditions
bronchospasm in reversible obstructive airway disease, such as acute and chronic asthma and chronic bronchitis.
They have also been effective in preventing exercise-induced bronchospasm.
Used also in Preterm labor
The SYMPATHOMIMETICS
CONTRAINDICATIONS/CAUTIONS
These drugs are contraindicated or should be used with caution, depending on the severity of the under- lying condition, in conditions that would be aggravated by the sympathetic stimulation.
Such conditions include cardiac disease, vascular disease, arrhythmias, diabetes, hyperthyroidism, pregnancy, and lactation.
The SYMPATHOMIMETICS
Pharmacodynamics: drug EFFECTS
Adverse effects of these drugs, which can be attributed to sympathomimetic stimulation include
CNS stimulation= tremors, headache, nervousness
GI- GI upset
Cardio= cardiac arrhythmias, hypertension, tachycardia and palpitations, vasoconstriction
Respi= bronchospasm, sweating, pallor, and flushing.
Hyperglycemia, Urinary retention
The SYMPATHOMIMETICS
Implementation
Assure the patient that the drug of choice will vary with each individual. These sympathomimetics are slightly different chemicals and are prepared in a variety of delivery systems.
Advise patients to use the minimal amount needed for the shortest period of time necessary, to prevent adverse effects and accumulation of drug levels.
The SYMPATHOMIMETICS
Implementation
Instruct the patient on how to use the inhalers. Teach patients who use one of these drugs for exercise-induced asthma to use it 30 to 60 minutes before exercising to ensure peak therapeutic effects when they are needed.
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Provide safety measures as needed if CNS effects become a problem, to prevent patient injury.
The SYMPATHOMIMETICS
Implementation
Provide small, frequent meals and nutritional consultation if GI effects interfere with eating to ensure, proper nutrition.
Carefully teach the patient about the proper use of the prescribed delivery system.
Review that procedure periodically as improper use may result in ineffective therapy.
The SYMPATHOMIMETICS
Evaluation
Monitor patient response to the drug (improved breathing).
Monitor for adverse effects (CNS effects, increased pulse and blood pressure, GI upset)
INHALED STEROIDS
Inhaled steroids have been found to be a very effective treatment for bronchospasm.
Agents include
Beclomethasone = given via MDI inhaler
Flunisolide
Triamcinolone
Dexamethasone= is given IV and orally, not inhaled
Prednisone and prednisolone
INHALED STEROIDS
THERAPEUTIC ACTIONS AND INDICATIONS
Inhaled steroids are used to decrease the inflammatory response in the airway.
In an airway swollen and narrowed by inflammation and swelling, this action will increase airflow and facilitate respiration.
Inhaling the steroid tends to decrease the numerous systemic effects that are associated with steroid use.
INHALED STEROIDS
THERAPEUTIC ACTIONS AND INDICATIONS
When administered into the lungs by inhalation, steroids decrease the effectiveness of the inflammatory cells.
This has two effects:
decreased swelling associated with inflammation
and promotion of beta adrenergic receptor activity= which may promote smooth muscle relaxation and inhibit broncho-constriction.
INHALED STEROIDS
CONTRAINDICATIONS/CAUTIONS
Inhaled corticosteroids are not for emergency use and not for use during an acute asthma attack or status asthmaticus.
They should not be used during pregnancy or lactation.
INHALED STEROIDS
ADVERSE EFFECTS
Adverse effects are limited because of the route of administration
Respiratory= Sore throat, hoarseness, coughing, dry mouth, and pharyngeal and laryngeal fungal infections are the most common side effects encountered.
If a patient does not administer the drug appropriately or develops lesions that allow absorption of the drug, the systemic side effects associated with steroids may occur.
INHALED STEROIDS
Implementation
Do not administer the drug to treat an acute asthma attack or status asthmaticus, as these drugs are not intended for treatment of acute attack.
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Taper systemic steroids carefully during the transfer to inhaled steroids; deaths have occurred from renal insufficiency with sudden withdrawal.
Have the patient use decongestant drops before using the inhaled steroid to facilitate penetration of the drug if nasal congestion is a problem.
INHALED STEROIDS
Implementation
Have the patient rinse the mouth after using the inhaler, as this will help to decrease systemic absorption and decrease GI upset and nausea
Monitor the patient for any sign of respiratory infection; continued use of steroids during an acute infection can lead to serious complications related to the depression of the inflammatory and immune responses.
INHALED STEROIDS
Evaluation
Monitor patient response to the drug (improved breathing).
Monitor for adverse effects (nasal irritation, fever, GI upset)
Cromolyn
Administered by INHALATION is a drug that is frequently used in the treatment of asthma.
It does not have bronchodilating or anticholinergic effects and does not fit into any other pharmacological class.
Cromolyn
THERAPEUTIC ACTIONS AND INDICATIONS
Cromolyn is a mast cell stabilizer.
It works at the cellular level to inhibit the release of histamine (released from mast cells in response to inflammation or irritation).
It is inhaled from a capsule and may not reach its peak effect for 1 week.
It is recommended for the treatment of chronic bronchial asthma, exercise-induced asthma, and allergic rhinitis.
Cromolyn
CONTRAINDICATION / CAUTIONS
Cromolyn cannot be used during an acute attack, and patients need to be instructed in this precaution.
Allergy to seafoods
It is not recommended for pregnant or nursing women or children under the age of 6 years.
Cromolyn
ADVERSE EFFECTS
Few adverse effects have been reported with the use of cromolyn
swollen eyes, headache, dry mucosa, and nausea.
Cromolyn
Implementation
Review administration procedures with the patient periodically; proper use of the delivery device is important in maintaining the effectiveness of this drug.
Caution the patient not to discontinue use abruptly; cromolyn should be tapered slowly if discontinuation is necessary to prevent rebound adverse effects.
Caution the patient to continue taking this drug, even in symptom-free periods, to ensure therapeutic levels of the drug.
Cromolyn
Implementation
Administer oral drug one-half hour before meals and at bedtime, which will promote continual drug levels and relief of asthma.
Advise the patient not to wear soft contact lenses; if cromolyn eye drops are used, lenses can be stained.
Provide thorough patient teaching, including the drug name and prescribed dosage, measures to help avoid adverse effects, warning signs that may indicate problems, and the need for periodic
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monitoring and evaluation to enhance patient knowledge about drug therapy and to promote compliance.
Cromolyn
Evaluation
Monitor patient response to the drug (improved breathing).
Monitor for adverse effects (drowsiness, headache, GI upset, local irritation).
Evaluate the effectiveness of the teaching plan (patient can name drug, dosage, adverse effects to watch for, specific measures to avoid adverse effects.
Anti-infective drugs
Selecting an anti-infective drug
First, the microorganism must be isolated and identified generally through growing a culture
Then its susceptibility to various drugs must be determined
Location of the infection must be considered
Cost of drugs as well as its potential adverse effects and allergies
Antibacterial drugs
Also known as antibiotics
Drugs that either kill or inhibit the growth of bacteria
Mainly used to treat systemic bacterial infections
Antibacterial drugs include:
1. aminoglycosides
2. cephalosporins
3. tetracyclines
4. lincomycin derivatives
5. macrolides
6. vancomycin
7. carbapenems
8. monobactams
9. fluoroquinolones
10. sulfonamides
11. nitrofurantoin
Aminoglycosides
Are bactericidal (destroy bacteria)
Effective against:
- gram-negative bacilli
- some aerobic gram-positive bacteria
- mycobacteria
- some protozoa
Currently in use includes:
- amikacin sulfate
- gentamicin sulfate
- kanamycin sulfate
- neomycin sulfate
- streptomycin sulfate
- tobramycin
Pharmacokinetics:
- absorbed poorly form the GIT
- usually given parenterally
- IV/IM absorption is rapid and complete
- distributed widely in extracellular fluid
- readily crossess the placental barrier but not BBB
- arent metabolized
- excreted primarily in the kidneys
Pharmacodynamics:
- by binding to the bacteria’s 30S subunit, specific ribosomes thereby interrupting CHON synthesis and causing the bacteria to die
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Pharmacotherapeutics:
- infections caused by gram-negative bacilli
- serious nosocomial, gram-negative bacteremia, peritonitis, pneumonia
- UTI’s
- infections of the CNS
Penicillins
Remain the most important and useful antibacterial drugs
Divided into four groups:
- natural penicillins ( penicillin G benzathine, penicillin G potassium, penicillin G procaine, penicillin G sodium, penicillin V potassium)
- penicillinase-resistant penicillines (dicloxacillin sodium, nafcillin sodium, oxacillin sodium)
- aminopenicillins (amoxicillin, ampicillin)
- extended-spectrum penicillins (carbenicillin indanyl sodium, ticarcillin disodium)
Pharmacokinetics:
- absorption of oral penicillin varies and depends on such factors as:
1. particular penicillin used
2. pH of the stomach and intestine
3. presence of food in the GIT
- most penicillins are given on an empty stomach (1 before or 2 hours after meal)
- penicillins that can be given wihtout regard to meals: amoxicillin, penicillin V and amoxicillin-clavulanate K
- most penicillins are excreted 60% unchanged by the kidneys (nafcillin and oxacillin – bile)
Pharmacodynamics:
- they bind reversibly to several enzymes (penicillin-binding proteins) outside the bacterial cytoplasmic membrane
Pharmacotherapeutics:
- wide spectrum
- they cover gram-positive, gram-negative, and anaerobic organisms
Cephalosporins
Are grouped into generations according to their effectiveness against different oraganisms, characteristics and development
First generation
Cefadroxil
Cefasolin
Cephalexin
cephadrine
Second generation
Cefaclor
Cefotetan
Cefprozil
Ceftibuten
cefuroxime
Third generation
Cefdinir
Cefoperazone
Cefotaxime
Ceftazidime
ceftriaxone
Fourth generation
Cefditoren
cefepime
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Are administered parenterally (they are’nt absorbed from the GIT)
Some are absorbed from the GIT but food usually decreases their absorption rate
Cefuroxime and cefpodoxime – increased absorption when given with food
Pharmacotherapeutics
- 1st generation – gram positive organisms
- used to treat staph and strep infections
- 2nd generation – gram – negative
- 3rd generation – drug of choice for enterobacter,P.
aeruginosa
- 4th generation – gram positive and
negative
Tetracyclines
Broad-spectrum antibacterial
Classified as:
- intermediate acting (demeclocycline Hcl)
- long acting (doxycycline and minocycline)
Pharmacokinetics:
- absorbed from the duodenum when taken orally
- distributed widely into body tissues and fluids concentrated in bile
- excreted primarily by kidneys
- doxycycline – feces
- minocycline – enterohepatic recirculation
Pharmacodynamics:
- they penetrate the bacterial cell by an energy-dependent process
- within the cell, they bind primarily to a subunit of the ribosome, inhibiting the CHON synthesis required for maintaining the bacterial cell
Pharmacotherapeutics:
- gram-positive/negative aerobic and anaerobic bacteria
- spirochettes
- mycoplasma
- rickettsiae
- chlamydia
- some protozoa
- tetracyclines are used to treat:
1. rocky mountain spotted fever
2. Q fever
3. lyme dse.
Macrolides
Includes erythromycin and derivatives such as:
- estolate
- ethylsuccinate
- gluceptate
- lactobionate
- stearate
Other macrolides includes:
- azithromycin
- clarithromycin
Pharmacokinetics:
- acid-sensitive (it must be buffered or have an enteric coating to prevent destruction by gastric acid)
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- erythromycin – absorbed in the duodenum
- metabolized in the liver
- excreted in bile in high concentrations, small amounts are excreted in urine
Pharmacodynamics:
- inhibit RNA-dependent CHON synthesis by acting on a small portion of the ribosome
Pharmacotherapeutics:
- drug of choice for treating Mycoplasma pneumoniae infections as well as pneumoniae caused by Legionella pneumophila
Carbapenems
Are a class of beta-lactam antibacterials that includes:
- imipenem-cilastatin Na
- meropenem
- ertapenem
Quinolones
Structurally similar synthetic antibacterial drugs
Primarily administered to treat UTI’s, URTI, pneumonia, gonorrhea
Includes:
- ciprofloxacin
- gatifloxacin
- levofloxacin
- moxifloxacin
- norfloxacin
- ofloxacin
Sulfonamides
First effective systemic antibacterial drugs
Includes:
Co-trimoxazole (sulfamethoxazole and trimethoprim)
Sulfadiazine
sulfisoxazole
Sulfonamides
treat UTI
sulfamethazole(Gantanol)
Sulfixazole(Gantrisin)
sulfazaline( Azulfidine)
sulfamethazole and trimethoprim(Bactrim and Septra)
Sulfonamides
S/E;
nausea and vomiting (gastric irritation) decreased absorption of folacin
rash
malaise
blood dyscrasias
crystaluria(drug precipitation in acidic urine)
stomatitis , hypersensitivity and photosensitivity
Sulfonamides
I
increase OFI
maintain alkaline urine
monitor blood work – megaloblastic anemia(dec. folacin)
potentiates anticoagulant and oral hypoglycemic effects
Antiviral drugs
Used to prevent or treat viral infections ranging from influenza to HIV
Major antiviral drug classes used to treat systemic infections include:
Synthetic nucleosides
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Nucleoside analog reverse transcriptase inhibitors (NRTIs)
Non-nucleoside reverse transcriptase inhibitors(NNRTIs)
Nucleotide analog reverse transcriptase inhibitors
Protease inhibitors
ANTIVIRALS
PROVIDE PROPHYLAXIS WHEN EXPOSURE TO VIRAL INFECTION HAS OCCURRED
Acyclovir sodium (Zovirax)
Amantadine Hcl (Symmetrel)
Interferon(Roferon – A)
AZT
Idoxuridine ( Stoxil)
ANTIVIRALS
cns stimulation and orthostatic hypotension, nephrotoxicity, dizziness and constipation
Nsg. Consideration:
support natural defense
encourage high fiber foods
evaluate response
Synthetic nucleosides
Group of drugs used to treat various viral syndromes that can occur in immunocompromised patients including HSV and CMV
Drugs in this class includes:
Acyclovir
Famciclovir
Ganciclovir
Valacyclovir Hcl
Valgancyclovir Hcl
ANTIVIRALS
PROVIDE PROPHYLAXIS WHEN EXPOSURE TO VIRAL INFECTION HAS OCCURRED
Acyclovir sodium (Zovirax)
Amantadine Hcl (Symmetrel)
Interferon(Roferon – A)
AZT
Idoxuridine ( Stoxil)
ANTIVIRALS
cns stimulation and orthostatic hypotension, nephrotoxicity, dizziness and constipation
Nsg. Consideration:
support natural defense
encourage high fiber foods
evaluate response
Anti Tuberculars
administered in combination over a prolonged time period to decrease the possibility of mycobacterial drug resistance
first line :
ethambutol-mycobacterial RNA
Isoniazid – mycobacterial cell wall
Paraaminosalicylic acid preparation(PAS)-mycobacterial folic acid synthesis
Rifampin-interferes with mycobacterial RNA
Streptomycin sulfate – inhibits mycobacterial protein synthesis
second line:
pyrazinamide
ethionamide
capriomycin
Anti Tuberculars
S/E:
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GI irritation
suppressed absorption of fat and B complex , -spec. folacin and B12, depletion of B6 by isoniazid
dizziness,CNS and liver disturbances
blod dyscrasias
streptomycin : ototoxicity( direct auditory{eight cranial nerve}toxicity)
ethambutol: visual disturbances ( direct optic nerve toxicity)
Anti Tuberculars
nursing care:
support defense mechanisms
obtain sputum specimens for acid fast bacillus
monitor blood work
enforce compliance , avoid alcohol
instruct regarding nutriitonal deficits
Rifampin – urine dark orange
Streptomycin: auditory exams
Ethambutol – visual exams
PZA – liver functions
Anti fungals
used to treat sytemic and localized fungal infections
Amphotericin ( Fungizone)
Fluconazole (Diflucan )
Griseofulvin ( Grisactin )
Nystatin ( Mycostatin, Nilstat )
Anti - fungals
nausea and vomiting( gastric irritation)
headache( neurotoxicity)
fever and chills ( blood dyscrasias )
paresthesia( neurotoxicity)
review proper method of application
assess vital signs, throughout course of therapy
evaluate clients response
Anti fungals
Amphotericin B
use infusion control device and protect from light
monitor blood works-hypokalemia and hypomagnesemia
Griseofulvin – assess for antagonism if patients are taking anti coagulants. avoid sunlight
topical prep- wash drug stained clothing with soap and water., report signs of local irritation
Anti parasitics
interfere with parasite metabolism and reproduction, helminthic as well as protozoal infestations respond to this class of drugs
Antihelmithic
Mebendazole ( Vermox)
Piperazine ( Vermazine )
Pyrivinium Pamoate ( Povan)
Amebicides
Chloroquine HCl ( Aralen)
Emetine Hcl
Metronidazole ( Flagyl)
Antimalarials
Chloroquine HCl ( Aralen)
Hydroxychloroquine SO4 ( Plaquenil)
Pyrimethamine ( Darapime)
Primaquine PO4
Anti parasitics
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antihelminthics-GI irritation, CNS disturbance, skin rash
amebicides – GI iiritation, blood dyscrasias, skin rash, headache, dizziness
Antimalarials-nausea and vomiting, blood dyscrasias, visual disturbances
Anti parasitics
administer drug with meals and assess VS
monitor blood works and instruct client about proper hygiene
use safety precautions if CNS effects are manifested
antimalarials – frequent visual examinations
evaluate response to treatment and understanding of therapy
Pharmacology of the anti-inflammatory agents
ANTI-INFLAMMATORY AGENTS
The anti-inflammatory response is designed to protect the body from injury and pathogens.
It employs a variety of potent chemical mediators to produce the reaction that helps to destroy pathogens and promote healing
Inflammatory Physiology
Inflammation: ETIOLOGY
Physical Agents
Mechanical objects causing trauma to objects
excessive heat & cold (burn & frostbite)
radiation
Chemical Agents
external irritants – strong acids, alkalis, irritating gasses
internal irritants – substances manufactured within the body such as excessive HCL in the stomach
Microorganisms – group of bacteria, viruses, fungi, protozoa, Rickettsia
Inflammation
Characteristic Signs:
Pain (Dolor)
Swelling /Edema (Tumor)
Redness (Rubor)
Heat (calor)
Impaired function of the part (severe injury) Functio laesa
Fig. 4.9
ANTI-INFLAMMATORY AGENTS
There are many different types of drugs utilized as anti-inflammatory agents.
Steroids like cortisone, beclomethasone, etc, systemically block inflammatory and immune responses.
Anti-histamines block the release of Histamine.
Another major class of drugs is termed Non-Steroidal Anti-inflammatory drug.
Drugs
The Salicylates
These agents are some of the oldest anti-inflammatory and pain reliever agents.
Acetylsalicylic acid (aspirin)
Choline magnesium trisalicylate
Choline salicylate
Mesalamine
Osalazine
Salsalate
Sodium thiosalicylate
Diflusinal (a derivative of salicylic acid)
Salicylates
Classification: Non-Steroidal Anti-inflammatory agents
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Dynamics: Inhibit the enzyme that produces prostaglandins
Kinetics: Administered orally and parenterally
Common side-effects Peptic ulceration, bleeding
NR: Administer with foods; bleeding precaution
Salicylates
Given for pain, fever and inflammation
Effectiveness is determined if manifestations of pain, fever and inflammation resolve.
The Salicylates
Mechanism of Action of the Salicylates
Salicylates inhibit the synthesis of prostaglandin, an important mediator of the inflammatory reaction.
The Salicylates
Mechanism of Action of the Salicylates
The fever lowering property (antipyretic effect) of salicylates is related to the blocking of a prostaglandin mediator of pyrogens
Aspirin affects platelet aggregation by inhibiting the synthesis of thromboxane A, a potent vasoconstrictor normally increases platelet aggregation
The Salicylates
Therapeutic Use of the Salicylates
Mild to moderate pain
Fever
Inflammatory conditions
Prevention of ischemic stroke
Aspirin is also given to patients with CAD, angina or previous history of MI to reduce the risk of myocardial infarction and death
The Salicylates
Pharmacokinetic profile of the Salicylates
Aspirin is well absorbed from the GIT.
Because of the GI effects, the Salicylates should be taken with meals
The Salicylates
The Adverse Effects of Salicylate Use
GIT- gastric ulceration , nausea, dyspepsia, heartburn and epigastric discomfort.
VASCULAR- bleeding abnormalities can be expected. Patients can have occult blood loss and spontaneous small hemorrhages.
The Salicylates
The Adverse Effects of Salicylate Use
SALICYLISM- this condition can occur with higher levels of aspirin. Acute salicylate toxicity may occur at 20 to 25 grams dosage intake in an adult, or about 4 grams in children
The Salicylates
Acute MILD Salicylism early sings/symptoms- Manifestations are ringing in the ear, dizziness, mild bronchospasm, nausea, vomiting, mental confusion and lassitude.
Acute SEVERE Salicylism late signs/symptoms- Metabolic ACIDOSIS, tachypnea, respiratory ALKALOSIS, hemorrhage, pulmonary edema, pyrexia, coma convulsions, and shock, hypo tension and multiple organ collapse (renal, cardiovascular and respiratory)
The Salicylates
Contraindications and Cautions with Salicylate Use
The use of Salicylates is contraindicated in the presence of known allergy to Salicylates, NSAIDs, and tartrazine. Impaired kidney function, pregnant and lactating women should avoid aspirin
A condition known as Reye’s syndrome can possibly occur if children and adolescents are given aspirin during a viral illness like chicken pox and influenza.
The Salicylates
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Nursing interventions for the Salicylates
Administer Salicylates WITH FOOD if GI upset is likely. Provide small, frequent meals to alleviate GI effects
Administer drug as indicated and monitor therapy to prevent toxicity
Monitor for severe drug effects= Tinnitus!!
Provide supportive care and comfort measures to support the effects of Salicylates in relieving pain and inflammation
The Salicylates
Nursing interventions for the Salicylates
For aspirin toxicity, the doctor orders sodium bicarbonate to ALKALINIZE the urine for faster drug excretion
The NSAIDS
Popularly called the NSAIDs, these agents are the most commonly used drugs for inflammation and pain.
The groups of NSAIDs are:
Salicylates
Propionic Acids and derivatives
Fenoprofen
Flurbiprofen
Ibuprofen
Ketoprofen
Naproxen
Oxaprozin
The NSAIDS
The groups of NSAIDs are:
Acetic Acids
Diclofenac (phenylacetic)
Etodolac (phenylacetic)
Ketorolac (phenylacetic)
Para-Chlorobenzoic Acid (indoles)
Indomethacin (chlorobenzoic acid)
Nabumetone (chlorobenzoic acid)
Sulindac (chlorobenzoic acid)
Tolmetin (chlorobenzoic acid)
Fenamates- Anthranilic acids
Mefenamic acid
Meclofenamate
Diflusinal
Piroxicam
The NSAIDS
Mechanism of Action of the NSAIDs
The anti-inflammatory, analgesic, and antipyretic effects are largely related to inhibition of prostaglandin synthesis.
The NSAIDS
Mechanism of Action of the NSAIDs
The NSAIDs block two enzymes known as cyclooxygenase-1 (COX-1) and cyclooxygenase-2 (COX-2) to stop turning arachidonic acid into prostaglandin.
The NSAIDS
Mechanism of Action of the NSAIDs
By interfering with this part of the inflammatory reaction, NSAIDs block inflammation before all of the signs and symptoms can develop
The NSAIDS
Therapeutic Use of NSAIDs
Moderate to severe pain
Inflammatory conditions like rheumatoid arthritis, osteoarthritis
Primary dysmenorrhea
Sometimes, for fever reduction
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The NSAIDS
Contraindication and Cautions with the use of NSAIDs
Allergy to any NSAID or salicylate; with cardiovascular dysfunction or hypertension due to the varying effects of prostaglandins;
With peptic ulcer or known GI bleeding because of the potential exacerbation; and during pregnancy and lactation because of potential effects on the baby
The NSAIDS
The Adverse Effects of NSAIDs
GIT- patients experience peptic Ulceration, dyspepsia, GI pain, constipation or diarrhea, and flatulence. The potential for GI bleeding should alert the nurse.
CNS- Patients may complain of dizziness, somnolence and fatigue.
VASCULAR- bleeding and bone marrow depression have been reported in chronic users.
The NSAIDS
The Selective COX-2 inhibitors- Second generation NSAIDs
Because older NSAIDs inhibit both the COX-1 and COX-2, they produce more side effects.
By inhibiting COX-1, protection of stomach lining is decreased and the clotting time is also decreased.
The selective COX-2 inhibitors only inhibit COX-2 present in inflammatory cells; thereby the GI effects are minimal.
The NSAIDS
The Selective COX-2 inhibitors- Second generation NSAIDs
Examples are: The “COXIB”s
CELECOXIB (Celebrex)
ROFECOXIB
NIMESULIDE
The NSAIDS
IMPLEMENTATION
Assure proper drug administration
Administer with food if GI upset will occur
Provide supportive and comfort measures to deal with adverse effects: small frequent meals, safety measures if dizziness occurs, etc.
Provide patient teaching regarding drug, dosage, side effects, precaution and warnings
The NSAIDS
IMPLEMENTATION
Remind the patient that piroxicam can take up to 2 weeks before therapeutic effect can be seen
The NSAIDS
EVALUATION
Evaluate drug effects such as decreasing pain and subsiding inflammatory response
Monitor for adverse effects
Monitor for drug-drug interaction
NSAIDS
N= o alcohol, aspirin
S= ide effects: “BIRTH”
B-one marrow depression, BLEEDING,
I-ncreased GI distress, R- renal toxicity, T- tinnitus and H- hepatotoxicity
A= aspirin sensitivity= Don’t give NSAIDS
I= Inhibits prostaglandin
D= Do TAKE with food
S= top 5-6 days before surgery
Paracetamol
Acetaminophen is widely used to treat moderate pain and fever when aspirin and NSAIDs cannot be utilized
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Paracetamol
Acetaminophen lacks an anti-inflammatory property that makes it ineffective for inflammation.
Paracetamol
Mechanism of Action of Acetaminophen
Acetaminophen acts directly on the thermoregulatory cells in the hypothalamus to cause sweating and vasodilation; this in turn causes the release of heat and lowers fever.
Analgesic action is still unclear
Paracetamol
Therapeutic use of Acetaminophen
Moderate pain
Fever
Prophylaxis of children receiving DPT immunization
Paracetamol
Contraindications and Precaution with the use of Acetaminophen
Acetaminophen is contraindicated in the presence of allergy to the drug.
Hepatic dysfunction and chronic alcoholism are important consideration.
Paracetamol
Adverse Effects of Acetaminophen
CNS- headache
Liver- hepatotoxicity is a potential adverse effect that is usually fatal. This happens in drug overdose. N-acetylcysteine is the antidote
Hemolytic anemia, renal dysfunction, skin rash
NARCOTIC AGONISTS
These are called agonists because they react with the opiod receptors throughout the body to cause analgesia, sedation and euphoria.
NARCOTIC AGONISTS
The following are examples of narcotic agonists
Morphine
Codeine
Meperidine
Methadone
Fentanyl
NARCOTIC AGONISTS
Therapeutic Use of Narcotic Agonists
Sedation
Analgesia
Antitussives
Adjunct to general anesthesia
Pain, acute and chronic pain
Pre-operative medication
NARCOTIC AGONISTS
Contraindications and Cautions: Use of Narcotics
The narcotic agonists are contraindicated in the following conditions: allergy to narcotics, pregnancy, labor and lactation because of potential effects on the fetus/neonate including respiratory depression, diarrhea caused by poisons and following biliary surgery.
NARCOTIC AGONISTS
Adverse Effects of the Narcotic Agonist
CNS- respiratory depression, sedation, lightheadedness, hallucinations, dizziness, anxiety, psychoses, pupil CONSTRICTION
GIT- Nausea, vomiting (due to the stimulation of the chemoreceptor trigger zone), constipation (due to decreased GIT motility) and biliary spasm (esp. morphine)
GU – ureteral spasms, urinary retention, hesitancy, and loss of libido. These may be due to the direct receptor stimulation or to CNS activation of sympathetic pathways.
Triad of OPIOID toxicity
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Respiratory depression
Coma
PIN POINT pupils
NARCOTIC AGONISTS
IMPLEMENTATION
Provide a narcotic antagonist and equipment for ventilation on standby to support the patient in case of severe reaction
Monitor timing of analgesic doses because prompt administration may provide a more acceptable level of analgesia leading to quicker relief of pain.
Utilize additional measures to relieve pain such as back rub, massage, stress reduction, hot/cold packs to increase the effectiveness of narcotic use and reduce pain.
NARCOTIC AGONISTS
IMPLEMENTATION
Assure patients that intake of medical doses of narcotics will NOT lead to addiction
Advise to eat a high-fiber diet with liberal intake of fluids to combat constipation
NARCOTIC AGONISTS
IMPLEMENTATION
Assure patients that intake of medical doses of narcotics. Warn patients about orthostatic hypotension and sedation so as to modify their activities like driving , performing delicate tasks and operating machineries
Take the drug with food may alleviate loss of appetite and nausea.
Advise patient to avoid use of alcohol, anti-histamine and other over-the counter drugs while taking narcotics.
NARCOTIC AGONISTS
EVALUATION
Monitor the response of the patient to the drug such as relief of pain, sedation and cough suppression
The NARCOTIC AGONIST-ANTAGONIST
These drugs stimulate certain opiod receptors but BLOCK other receptors
They have less abuse potential than pure narcotic agonists but their analgesic properties may be equal.
The NARCOTIC AGONIST-ANTAGONIST
The following are the narcotic agonists-antagonist:
Buphenorphine
Butorphanol
Dezocine
Nalbuphine (Nubain)
Pentozacine
The NARCOTIC AGONIST-ANTAGONIST
Mechanism of Action of Narcotic Agonist-Antagonist
The mixed narcotics act at specific opiod receptor sites in the CNS to produce analgesia, sedation, euphoria and hallucinations.
They also block opiod receptor that may be stimulated by the pure agonists.
The NARCOTIC AGONIST-ANTAGONIST
Therapeutic Use of Mixed Narcotics
Relief of moderate to severe pain
Addition to general anesthesia
Relief of pain labor and delivery
The NARCOTIC AGONIST-ANTAGONIST
Adverse Effects of the Mixed Narcotics
Respiratory depression with apnea and suppression of the cough reflex
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Nausea and vomiting are due to the stimulation of the CTZ
Constipation due to impaired GIT motility and Biliary spasms due to stimulation of bile duct contraction
CNS opiod receptor stimulation will cause: hallucination, sedation, euphoria lightheadedness, dizziness, psychoses, anxiety, and impaired mental processes
GU effects are urinary hesitancy, retention, loss of libido and ureteral spasms.
The NARCOTIC AGONIST-ANTAGONIST
IMPLEMENTATION
Provide a narcotic antagonist and equipment for resuscitation in cases of very severe reactions to provide supportive care
Institute comfort measures and safety precautions such as side rails, assistance in ambulation, bowel program and small frequent meals
The NARCOTIC AGONIST-ANTAGONIST
IMPLEMENTATION
Provide additional pain relieving measures such as hot/cold packs, stress reduction, massage and back rubs
Assure patients that addiction is very minimal
Provide client teaching including drug name, prescribed dosage, measures to handle adverse effects, warning sings and the need for regular evaluation
The NARCOTIC ANTAGONISTS
These are drugs that bind strongly to opiod receptors but DO NOT activate them.
The following are the narcotic antagonists:
Nalmefene
Naloxone
Naltrexone
The NARCOTIC ANTAGONISTS
The Mechanism of Action of Narcotic Antagonist
The narcotic antagonists block opioid receptors and reverse the effects of opoids, including respiratory depression, sedation, and psychomimetic effects.
The NARCOTIC ANTAGONISTS
Therapeutic Use of narcotic antagonists
Reversal of the effects of narcotics and over dosage- naloxone and nalmefene are used to manage these conditions.
Naloxone is used to diagnose narcotic overdose using the naloxone challenge test
Narcotic dependence and alcoholic dependence- naltrexone is used in the management of these conditions.
The NARCOTIC ANTAGONISTS
The Adverse Effects of Narcotic Antagonists
The most common is acute narcotic abstinence syndrome that is characterized by nausea, vomiting, sweating, tachycardia, hypertension, tremulousness, and anxiety.
CNS- excitement and reversal of analgesia
CV effects- tachycardia, blood pressure changes, arrhythmias and pulmonary edema.
The NARCOTIC ANTAGONISTS
IMPLEMENTATION
Maintain open airway and provide artificial ventilation and cardiac massage as needed in severe reaction
Administer naloxone challenge before giving naltrexone because of serious risk of acute withdrawal
Monitor patient continually adjusting the dosage as needed during treatment of acute overdose
The NARCOTIC ANTAGONISTS
IMPLEMENTATION
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Ensure that patient is receiving naltrexone as part of a comprehensive or alcohol withdrawal program
Institute comfort measures such as side rails, assistance with ambulation, bowel program, environmental stimulation control and small frequent feedings to relieve GI irritation.
ANTIGOUT
Gout is a metabolic disease characterized by inflammation of the joints and deposition of uric acid crystals in other parts of the body.
The joint most commonly affected is the metatarsal joint of the big toe.
The etiologies of gout may be increased accumulation of uric acid or ineffective clearance of uric acid in the kidney.
Drugs for Gout
ANTIGOUT: Colchicine
ANTI-INFLAMMATORY Gout Drug
Cochicine is an anti-inflammatory drug that inhibits the migration of leukocytes to the inflamed site. Its action is attribute to the inhibition of WBC microtubule assembly.
Indomethacin is also another drug used because it can reduce WBC migration and phagocytosisà decreased inflammation
ANTIGOUT: Colchicine
ANTI-INFLAMMATORY Gout Drug
It is effective in alleviating acute symptoms of gout but not in other conditions. It does not inhibit uric acid synthesis and does not promote uric acid excretion.
It is not recommended for clients with severe renal, cardiac or GI problems.
Gastric irritation is a common problem and it should be taken with food. Other side effects are Nausea, vomiting, diarrhea, abdominal pain.
ANTIGOUT
URIC ACID INHIBITOR: ALLOPURINOL
Allopurinol is the drug given to patients to reduce the uric acid synthesis.
It is used frequently as prophylaxis to prevent gouty attacks.
ANTIGOUT
URIC ACID INHIBITOR: ALLOPURINOL
Allopurinol
Increased fluid intake is recommended to promote diuresis and prevent alkalinization of the urine.
Nurses must encourage at least 3 liters of fluid per day.
ANTIGOUT
Pharmacodynamics: Action of Allopurinol
This drug inhibits the production of uric acid by inhibiting the enzyme xanthine oxidase. This also improves the solubility of the uric acid crystals.
Onset of action is 1 hour, and peak is 2-4 hours. The effect of the drug may not be apparent for few days to a few weeks.
Nurses must teach this to the patient to avoid non-compliance.
ANTIGOUT
Pharmacokinetics
It is given orally in the management of gout. Majority of the drug is absorbed from the GIT. The half-life is 2-3 hours.
Most of the drugs and metabolites are excreted in the feces and some in the urine. Its onset of action is 1 hour and peak is 2-4 hours.
ANTIGOUT
Adverse Effects
GIT- anorexia, nausea, vomiting, diarrhea and stomatitis.
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CNS- dizziness, peripheral neuritis and vasculitis
Acute gouty attacks if allopurinol is given during the acute stage of the disease.
Reportable manifestations are rashes and swelling.
ANTIGOUT: Allopurinol
Patient should be warned not to drink alcoholic beverages and to avoid foods that are rich in uric acid- aged foods, legumes, beer, internal organ meats.
Increase fluid intake to 3 liters per day
Report occurrence of rashes
Take with meals
Allopurinol and Gout
G= ulp 10-12 glasses of fluid/day. GI distress is undesirable
O=utput and input should be monitored closely
U=ric acid production decreases and USE NO ALCOHOL
T=ake AFTER meals when stomach is full
ANTIGOUT
URICOSURIC DRUGS: Probenecid
These agents are weak acids and can cause increased excretion of uric acids in the kidney by competing with uric acid, thus inhibiting its re-absorption
They are effective in alleviating chronic gout but they are not used in acute attacks.
ANTIGOUT
URICOSURIC DRUGS
Probenecid- is a uricosuric agent that blocks the re-absorption of uric acid and promotes its excretion.
It causes gastric irritation and should be taken with meals.
ANTIGOUT
URICOSURIC DRUGS
Sulfinpyrazone- a metabolite of phenylbutazone is more potent than probenecid.
It should also be taken with meals because of gastric irritation.
Severe blood dyscrasias can occur.
GOLD compounds
Chrysotherapy (heavy metal therapy) is the treatment of these rheumatic conditions with the use of gold compounds.
GOLD compounds
There are currently 3 gold compounds for use:
Auranofin- is an oral agent used for long-term therapy
Aurothioglucose- parenteral gold IM preparation given in early disease
Gold Sodium Thiomalate- also a parenteral IM preparation of gold salts
GOLD compounds
The Mechanism of action of Gold Salts
Gold salts are ingested by macrophages and inflammatory cells resulting in the inhibition of phagocytosis.
It depresses the migration of leucocytes and suppress prostaglandin activity
GOLD compounds
It is important for the nurse to remember that the therapeutic effect of these agents can take up to 8 weeks or 2 months (if given parenterally) or 3-6 months (if given orally)
GOLD compounds
The Adverse Effects of Gold Compounds
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Tissue/local effects- these are associated with the deposition of the gold metal in the tissues. Stomatitis, dermatitis, glossitis, pharyngitis, laryngitis, colitis, diarrhea and GIT inflammation.
Other effects- Hypersensitivity, BONE MARROW DEPRESSION , RENAL INSUFFICIENCY and anaphylaxis
Nurses must instruct the patient to report metallic taste in the mouth as it signals toxicity.
GOLD compounds
Nursing Responsibilities
Monitor CBC, urinalysis and liver enzymes
Teach the client to avoid strong lights to prevent dermatitis
Proper oral care to manage stomatitis
Explain to patients that therapeutic effect can be expected after several months of intake and administration
STEROIDS
Replaces the steroids in the body
Cortisol, cortisone, betamethasone, and hydrocortisone
STEROIDS
These drugs enter the cells and bind to receptors
They inhibit the enzyme phospholipase
STEROIDS
Corticosteroids are used topically and locally to achieve the desired anti-inflammatory effects at a particular site
Examples:
Prednisone
Bethamethasone
Prednisolone
Fludrocortisone
STEROIDS
Side-effects
HYPERglycemia
Increased susceptibility to infection (immunosuppression)
Hypokalemia
Edema
Peptic ulceration
STEROIDS
Side-effects
If high doses- osteoporosis, growth retardation, peptic ulcer, hypertension, cataract, mood changes, hirsutism, and fragile skin
STEROIDS
Nursing responsibilities
1. Monitor VS, electrolytes, glucose
2. Monitor weight edema and I/O
STEROIDS
Nursing responsibilities
3. Protect patient from infection
4. Handle patient gently
5. Instruct to take meds WITH MEALS to prevent gastric ulcer formation
STEROIDS
Nursing responsibilities
6. Caution the patient NOT to abruptly stop the drug
7. Drug is tapered to allow the adrenal gland to secrete endogenous hormones
STEROIDS
Evaluation:
The drugs are effective if there is:
1. Relief of signs and symptoms of inflammation
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2. Return of adrenal function to normal
Pharmacology of the GIT system
LECTURE Outline
REVIEW the Anatomy of the GIT
REVIEW the Physiology of the GIT
Review common GI drugs in the following categories:
1. Drugs affecting GI secretions
2. Laxatives
3. Anti-diarrheals
4. Emetics and anti-emetics
Drugs affecting GI secretions
There are five types of drugs that affect gastric acid secretions and are useful for the treatment of peptic ulcer.
1. Histamine (H2) receptor antagonist/blockers
2. Antacids
3. Proton pump inhibitors
4. Mucosal protectants
5. Prostaglandin analogs
Drugs affecting secretions: anti ulcer
General indication of the drugs affecting gastric acid secretion
Peptic ulcer
Gastritis
Patient on NPO to prevent stress ulcer
General time of administration of the drugs affecting gastric acid secretion
Pharmacodynamics
Histamine (H2) receptor blockers
These drugs BLOCK the release of hydrochloric acid in the stomach in response to gastrin
Drugs affecting GI secretions
Antacids
These drugs interact with the gastric acids at the chemical level to neutralize them
Drugs affecting GI secretions
Proton pump inhibitors
These drugs suppress the secretion of hydrochloric acid into the lumen of the stomach
Drugs affecting GI secretions
Mucosal protectants
These are agents that coat any injured area in the stomach to prevent further injury from acid
Drugs affecting GI secretions
Prostaglandin analogs
These are agents that inhibit the secretion of gastrin and
increase the secretion of mucus lining of the stomach, providing a buffer.
The H2 Blockers- “tidines”
Prototype: Cimetidine
1. Ranitidine
2. Famotidine
3. Nizatidine
The H2 Blockers- “tidines”
Pharmacodynamics: Drug Action
The H2 blockers are antagonists at the receptors in the parietal cells of the stomach.
The blockage results to inhibition of the hormone gastrin.
There will be decreased production of gastric acid from the parietal cells.
Also, the chief cells will secrete less pepsinogen.
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The H2 Blockers- “tidines”
Therapeutic use of the H2 blockers
Short-term treatment of active duodenal ulcer or benign gastric ulcer
Treatment of hypersecretory conditions like the Zollinger-Ellison syndrome
Prevention of stress-induced ulcers and acute GI bleeding
Treatment of erosive GERD (reflux disease)
Relief of Symptoms of heart burn and acid indigestion
The H2 Blockers- “tidines”
Precautions and Contraindications
Any known allergy is a clear contraindication to the use of the agents.
Conditions such as pregnancy, lactation, renal dysfunction and hepatic dysfunction should warrant cautious use.
Nizatidine can be used in hepatic dysfunction.
The H2 Blockers- “tidines”
Dynamics- Side effects/adverse effects
GIT= diarrhea or constipation
CNS= Dizziness, headache, drowsiness, confusion and hallucinations
Cardio= arrhythmias, HYPOTENSION (related to H2 receptor blockage in the heart)
Cimetidine= Gynecomastia and impotence in males
The H2 Blockers- “tidines”
Drug-drug Interactions
Cimetidine, Famotidine, Ranitidine are metabolized in the liver- they can cause slowing of excretion of other drugs leading to their increased concentration.
The H2 Blockers- “tidines”
Drug-drug Interactions
These drugs can interact with CIMETIDINE
Anticoagulants
Phenytoin,
Alcohol
Antidepressants.
The H2 Blockers- “tidines”
Nursing considerations:
Administer the drug WITH meals at BEDTIME to ensure therapeutic level
One hour after Antacids
Stress the importance of the continued use for the length of time prescribed
The H2 Blockers- “tidines”
Nursing considerations
Monitor the cardiovascular status especially if the drugs are given IV
Warn patient of the potential problems of increased drug concentration if the H2 blockers are used with other drugs or OTC drugs. Advise consultation first!
The H2 Blockers- “tidines”
Nursing considerations:
Provide comfort measures like analgesics for headache, assistance with ambulation and safety measures because of confusion
Warn the patients taking cimetidine that drowsiness may pose a hazard if driving or operating delicate machines.
The H2 Blockers- “tidines”
Nursing considerations:
Provide health teaching as to the dose, frequency, comfort measures to initiate when side-effects are intolerable
Evaluate the effectiveness
Relief of symptoms of ulcer, heart burn and GERD
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The Antacids
These are drugs or inorganic chemicals that have been used for years to neutralize acid in the stomach
The Antacids
The following are the common antacids that can be bought OTC:
Aluminum salts (hydroxide)
Calcium salts (carbonate)
Magnesium salts (milk of magnesia)
Sodium bicarbonate
Magaldrate (aluminum and magnesium combination)
The Antacids
Pharmacodynamics: drug action
These agents act to neutralize the acidic pH in the stomach.
They do not affect the rate of gastric acid secretion.
The Antacids
Pharmacodynamics: drug action
The administration of antacid may cause an acid rebound.
Neutralizing the stomach content to an alkaline level stimulates gastrin production to cause an increase in acid production and return the stomach to its normal acidic state.
The Antacids
Therapeutic Indications
Symptomatic relief of upset stomach associated with hyperacidity
Hyperacidic conditions like peptic ulcer, gastritis, esophagitis and hiatal hernia
Special use of AMPHOGEL (aluminum hydroxide): to BIND phosphate
The Antacids
Precautions of Antacid Use
Known allergy is a clear contraindication
Caution should be instituted if used in electrolyte imbalances, GI obstruction and renal dysfunction.
Sodium bicarbonate is rarely used because of potential systemic absorptionà metabolic alkalosis!!!
The Antacids
Pharmacokinetics
These agents are taken orally and act locally in the stomach
The Antacids
Pharmacodynamics: Effects of drugs
1. GIT= rebound acidity; alkalosis may occur.
Calcium salts may lead to hypercalcemia
Magnesium salts can cause DIARRHEA
Aluminum salts may cause CONSTIPATION and Hypophosphatemia by binding with phosphates in the GIT.
2. Fluid retention due to the high sodium content of the antacids.
The Antacids
Nursing Considerations:
Administer the antacids apart from any other medications by ONE hour before or TWO hours after- to ensure adequate absorption of the other medications
Tell the patient to CHEW the tablet thoroughly before swallowing. Follow it with one glass of water
Regularly monitor for manifestations of acid-base imbalances as well as electrolyte imbalances
The Antacids
Nursing Considerations:
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Provide comfort measures to alleviate constipation associated with aluminum and diarrhea associated with magnesium salts.
Monitor for the side-effects, effectiveness of the comfort measures, patient’s response to the medication and the effectiveness of the health teachings
The Antacids
Nursing Considerations
Evaluate for effectiveness:
Decreased symptoms of ulcer
Decreased Phosphate level (Amphogel) in patients with chronic renal failure
The PPI
These are the newer agents for ulcer treatment
The “prazoles”
Prototype: Omeprazole
Lansoprazole
Esomeprazole
Pantoprazole
The PPI
Pharmacodynamics: drug action
They act at specific secretory surface receptors to prevent the final step of acid production and thus decrease the level of acid in the stomach.
The “pump” in the parietal cell is the H-K ATPase enzyme system on the secretory surface of the gastric parietal cells
The PPI
Clinical use of the PPIs
Short-term treatment of active duodenal ulcers, GERD, erosive esophagitis and benign gastric ulcer
Long-term- maintenance therapy for healing of erosive disorders.
The PPI
Precautions with the use of the PPIs
Known allergy is a clear contraindication
Caution if patient is pregnant
The PPI
Pharmacodynamics: Adverse effects
CNS- dizziness, headache, asthenia (loss of strength), vertigo, insomnia, apathy
GIT- diarrhea, abdominal pain, nausea, vomiting, dry mouth and tongue atrophy
Respi- cough, stuffy nose, hoarseness and epistaxis.
The PPI
Nursing considerations:
Administer the drug BEFORE meals. Ensure that patient does not open, chew or crush the drug.
Provide safety measures if CNS dysfunction happens.
Arrange for a medical follow-up if symptoms are NOT resolved after 4-8 weeks of therapy.
The PPI
Nursing considerations:
Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.
Monitor patient response to the drug, the effectiveness of the teaching plan and the measures to employ
The PPI
Nursing considerations:
Evaluate for effectiveness of the drug
Healing of peptic ulcer
Decreased symptoms of ulcer
The Mucosal Protectant
Sucralfate (Caralfate/ Iselpin)
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This is given to protect the eroded ulcer sites in the GIT from further damage by acid and digestive enzymes
Sucralfate
Pharmacodynamics: Action of drug
It forms an ulcer-adherent complex at duodenal ulcer sites, protecting the sites against acid, pepsin and bile.
This action prevents further breakdown of proteins in the area and promotes healing.
Sucralfate
Clinical use of sucralfate
Short and long term management of duodenal ulcer.
NSAIDs induced gastritis
Prevention of stress ulcer
Treatment of oral and esophageal ulcers due to radiation, chemotherapy or sclerotherapy.
Sucralfate
Precautions on the use of Sucralfate
This agent should NOT be given to any person with known allergy to the drug, and to those patients with renal failure/dialysis because of build-up of aluminum may occur if used with aluminum containing products.
The Mucosal Protectant
Pharmacodynamics: Side-effects & adverse reactions
Primarily GIT= CONSTIPATION, occasionally diarrhea, nausea, indigestion, gastric discomfort, and dry mouth may also occur
CNS= dizziness, drowsiness, vertigo
Others= rash and back pain
The Mucosal Protectant
Drug-drug interactions
If used with aluminum salts= high risk of accumulation of aluminum and toxicity.
If used with phenytoin, fluoroquinolones and penicillamines- decreased levels of these drugs when taken with sucralfate
The Mucosal Protectant
Nursing Considerations
Administer drug ON AN EMPTY stomach, 1 hour before meals , or 2 hour after meals and at BEDTIME
Monitor for side-effects like constipation and GI upset
Encourage intake of high-fiber foods and increased fluid intake
Administer antacids BETWEEN doses of sucralfate, NOT WITHIN 30 minutes of sucralfate dose
The Mucosal Protectant
Nursing Considerations
Provide comfort measures if CNS effects occur
Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.
Monitor patient response to the drug, the effectiveness of the teaching plan and the measures employed
The Mucosal Protectant
Nursing Considerations
Evaluate effectiveness of therapy
Healing of ulcer
No formation of ulcer
Prostaglandin analogue
Misoprostol
This agent is a synthetic prostaglandin E1 analog that is employed to protect the lining of the mucosa of the stomach
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Prostaglandin analogue
Misoprostol: Pharmacodynamics
Being a prostaglandin analog, it inhibits gastric acid secretion to some degree
It INCREASES mucus production in the stomach lining.
Prostaglandin analogue
Misoprostol: Clinical use
NSAIDs-induced gastric ulcers
Duodenal ulcers unresponsive to H2 antagonists
Prostaglandin analogue
Precautions of Misoprostol Use
This drug is CONTRAINDICATED during pregnancy because it is an abortifacient.
Women should be advised to have a negative pregnancy test within 2 weeks of beginning therapy and should begin the drug on the second or third day of the next menstrual cycle.
They should be instructed in the use of contraceptives during therapy.
Prostaglandin analogue
Pharmacodynamic effects: drug reactions
GIT= Nausea, diarrhea, abdominal pain, flatulence, vomiting, dyspepsia
GU effects= miscarriages, excessive uterine CRAMPING and bleeding, spotting, hyper-menorrhea and menstrual disorders.
Prostaglandin analogue
Nursing Considerations
Administer to patients at risk for NSAIDs-induced ulcers during the full course of NSAIDs therapy
Administer four times daily with meals and at bedtime
Obtain pregnancy test within 2 weeks of beginning therapy.
Begin the therapy on second or third day of menstrual period to ensure that the woman is not pregnant
Prostaglandin analogue
Nursing Considerations
Provide patient with both written and oral information regarding the associated risks of pregnancy
Provide health teaching as to drug name, dosages and frequency, safety measures to handle common problems.
Monitor patient response to the drug, the effectiveness of the teaching plan and the measures to employ
Laxatives
Generally used to INCREASE the passage of the colonic contents
The general classifications is as follows:
1. Chemical stimulants- irritants
2. Mechanical stimulants- hyperosmotic agents and saline cathartics
3. Lubricants and stool softeners
Laxatives
They promote bowel evacuation for various purposes
They are classified into their mode of action
Laxatives
Therapeutic Indications of the Laxatives
SHORT term relief of Constipation
Prevention of straining in conditions like CHF, post-MI, post partum, post-op
Preparation for diagnostic examination
Removal of poison or toxins
Adjunct in anti-helminthic therapy
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To remove AMMONIA by use of lactulose
Contraindications in Laxative use
ACUTE abdominal disorders
Appendicitis
Diverticulitis
Ulcerative colitis
Chemical Stimulant Cathartics
Prototype: Bisacodyl
Irritant laxatives:
1. Castor oil
2. Senna
3. Cascara
4. Phenolphthalein
Chemical Stimulant Cathartics
Pharmacodynamics
These agents DIRECTLY stimulate the nerve plexus in the intestinal wall
The result is INCREASED movement or motility of the colon
Mechanical Stimulant Cathartics
Prototype: LACTULOSE (Cephulac)
Bulk-forming laxatives
1. Magnesium (citrate, hydroxide, sulfate)- saline cathartic
2. Psyllium
3. Polycarbophil
Mechanical Stimulant Cathartics
Pharmacodynamics
These agents are rapid-acting laxatives that INCREASE the GI motility by
Increasing the fluids in the colonic material
Stimulating the local stretch receptors
Activating local defecation reflex
Lubricants-Stool softener
Prototype: Docusate
1. Glycerin
2. Mineral oil
Lubricants-stool softeners
Pharmacodynamics
Docusate increases the admixture of fat and water producing a softer stool
Glycerin and Mineral oil form a slippery coat on the colonic contents
Pharmacokinetics: Common Side-effects of the Laxatives
Diarrhea
Abdominal cramping
Nausea
Fluid and electrolyte imbalance
Sympathetic reactions- sweating, palpitations, flushing and fainting
CATHARTIC dependence
The Nursing Process and Laxative
ASSESSMENT
Nursing History- elicit allergy to any laxatives, elicit history of conditions like diverticulitis and ulcerative colitis
Physical Examination- abdominal assessment
Laboratory Test: fecalysis, electrolyte levels
The Nursing Process and Laxative
NURSING DIAGNOSIS
Alteration in bowel pattern
Alteration in comfort: pain
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Knowledge deficit
The Nursing Process and Laxative
IMPLEMENTATION
1. Emphasize that it is use on a SHORT term basis
2. Provide comfort and safety measures like ready access to the bathroom, side-rails
3. Administer with a full glass of water
The Nursing Process and Laxative
IMPLEMENTATION
4. Encourage fluid intake, high fiber diet and daily exercise
5. DO NOT administer if acute abdominal condition like appendicitis is present
6. Advise to change position slowly and avoid hazardous activities because of potential dizziness
The Nursing Process and Laxative
IMPLEMENTATION
7. Record intake and output to assess fluid alteration
8. If possible, observe the character of stools
9. Caution the patient that chronic use may promote dependence and use during pregnancy may cause uterine cramping and Vitamin deficiency
The Nursing Process and Laxative
EVALUATION of drug effectiveness
1. Evaluate relief of GI symptoms, absence of staining and increased evacuation of GI tract
2. For Lactulose: decreased ammonia
3. Normal bowel function is restored
The Anti-diarrheals
These are agents used to calm the irritation of the GIT for the symptomatic relief of diarrhea
General Classifications
1. Local anti-motility
2. Local reflex inhibition
3. Central action on the CNS
The Anti-diarrheals
Clinical Indications of drug use
Relief of symptoms of acute and chronic diarrhea
Reduction of fecal volume discharges from ileostomies
Prevention and treatment of traveler's diarrhea
Contraindications of anti-diarrheal Use
Poisoning
Drug allergy
GI obstruction
Acute abdominal conditions
Pharmacokinetics: Side effects
Constipation
Nausea, vomiting
Abdominal distention and discomfort
TOXIC MEGACOLON
Nursing process and anti-diarrheals
ASSESSMENT
Nursing History – Elicit history of drug allergy, conditions like poisoning, GI obstruction and acute abdominal conditions
Physical Examination- Abdominal examination
Laboratory test- electrolyte levels
Nursing process and anti-diarrheals
NURSING DIAGNOSIS
Alteration in bowel pattern
Alteration in comfort: pain
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Nursing process and anti-diarrheals
IMPLEMENTATION
1. Monitor patient response within 48 hours. Discontinue drug use if no effect
2. Provide comfort measures for pain
3. Provide teaching regarding its short term use only
Nursing process and anti-diarrheals
EVALUATION
1. Monitor effectiveness of drug- RELIEF of diarrhea
2. Monitor adverse effects, effectiveness of pain measures and effectiveness of teaching plan
Emetics and Anti-emetics
Emetic Agent
Syrup of Ipecac
Anti-emetics
1. Phenothiazines
2. Non-phenothiazines
3. Anticholinergics/Antihistamines
4. Serotonin receptor Blockers
5. Miscellaneous
EMETIC
Prototype: Ipecac Syrup
EMETIC
Pharmacodynamics
Ipecac syrup irritates the GI mucosa locally, resulting to stimulation of the vomiting center
It acts within 20 minutes
EMETIC
Clinical Use of ipecac
To induce vomiting as a treatment for drug overdose and certain poisonings
EMETIC
Contraindications of Ipecac use
Ingestion of CORROSIVE chemicals
Ingestion of petroleum products
Unconscious and convulsing patient
EMETIC
Pharmacokinetics: side effects of Ipecac
Nausea
Diarrhea
GI upset
Mild CNS depression
CARDIOTOXICITY if large amounts are absorbed in the body
Nursing process and the EMETIC
ASSESSMENT
Nursing History- elicit the exact nature of poisoning
Physical Examination- CNS status and abdominal exam
Nursing process and the EMETIC
IMPLEMENTATION
1. Administer to conscious patient only
2. Administer ipecac as soon as possible
3. Administer with a large amount of water
4. Vomiting should occur within 20 minutes of the first dose. Repeat the dose and expect vomiting to occur within 20 minutes
Nursing process and the EMETIC
IMPLEMENTATION
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5. Provide comfort measures like ready access to bathroom, assistance with ambulation
6. Offer support
Nursing process and the EMETIC
EVALUATION
1. Evaluate patient response within 20 minutes of drug ingestion
2. Monitor for adverse effects
3. Evaluate effectiveness of comfort measures and teaching plan
ANTI-EMETICS
These are agents used to manage nausea and vomiting
They act either locally or centrally
In general, they may inhibit the chemoreceptor trigger zone in the medulla by blocking DOPAMINE receptor
ANTIEMETICS
ANTIEMETICS
ANTIEMETICS
ANTIEMETICS
Indications
1. Prevention and treatment of vomiting
2. Motion sickness
ANTIEMETICS
Contraindications
1. Severe CNS depression
2. Severe liver dysfunction
ANTIEMETICS
Pharmacokinetics:
Oral absorption is good if vomiting is not present
IV drugs can be given if vomiting is active
Most drugs are metabolized in the liver excreted in the kidneys
ANTIEMETICS
Pharmacokinetics: Side-effects
1. PHOTHOSENSITIVITY
2. Drowsiness, dizziness, weakness and tremors and DEHYDRATON
3. Phenothiazines= autonomic anti-cholinergic effects like dry mouth, nasal congestion and urinary retention
Metoclopramide= EPS due to dopamine receptor blockage
Nursing Process and the ANTIEMETICS
ASSESSMENT
Nursing History- elicit allergy, impaired hepatic function and CNS depression
Physical Examination- CNS status and abdominal examination
Laboratory test- Liver function studies
Nursing Process and the ANTIEMETICS
NURSING DIAGNOSIS
1. Alteration in comfort: pain
2. High risk for injury
3. Knowledge deficit
Nursing Process and the ANTIEMETICS
IMPLEMENTATION
1. Assess patient’s intake of other drugs that may cause dangerous drug interaction
2. Emphasize that this is given on a short term basis
Nursing Process and the ANTIEMETICS
IMPLEMENTATION
3. Provide comfort and safety measures
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Advise to change position slowly
Avoid hazardous activities
Provide mouth care and ice chips
Monitor for dehydration and offer fluids if it occurs
Nursing Process and the ANTIEMETICS
IMPLEMENTATION
4. Protect from sun exposure
Sunscreens
Protective covering
5. Provide health teaching
Nursing Process and the ANTIEMETICS
EVALUATION
1. Monitor for the drug effectiveness
• Relief of nausea and vomiting
2. Monitor for adverse effects
3. Evaluate effectiveness of comfort measures and teaching plan
CENTRAL NERVOUS SYSTEM DRUGS
CNS STIMULANTS: Overview
A. Description
- an effect that may be noted with use of many drugs
- actual indications for using CNS is limited
- includes amphetamines and amphetamine-like agents
B. Action
- stimulants enhance neurotransmitter activity in the CNS, particularly the cerebral cortex
- produces peripheral effects on BP, GI motility, vasoconstriction and pupillary dilation
C. Indications
- treatment of Narcolepsy
- treatment of attention deficit disorder with hyperactivity in children
- exogenous obesity
D. Overview of nursing interventions
- be aware that nursing interventions will vary depending on the intended effect
- provide client teaching based on the indication for using the drug
- note that the least amount possible of the drug should be prescribed at one time to minimize the possibility of overdosage
CNS STIMULANTS
CNS stimulants tend to produce an effect that increases energy or reduces fatique and associated symptoms
PHARMACODYNAMICS/ACTION
1. cause release of norepinephrine from its storage sites in adrenergic nerve terminals
2. effects of these agents may be similar to those of ephedrine
PHARMACOTHERAPEUTICS
- varies according to indications
PHARMACOKINETICS
1. most CNS stimulants are absorbed through the GI system
2. duration of action is variable
3. excretion occurs through the kidney
CONTRAINDICATIONS
1. in clients with symptomatic CV disease, hyperthyroidism, nephritis, angina pectoris, moderate to severe hypertension, types of glaucoma, and history of drug abuse
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2. used caution in clients with DM or seizure disorders, in elderly, hyperexcitable clients
DRUG INTERACTIONS
- vary among specific drugs
NURSING MANAGEMENT:
ASSESSMENT
a. assess client hx of drug abuse
b. review the complete history and physical examination
PLANNING AND IMPLEMENTATION
a. Monitor height and weight in children
b. Monitor for s/sx of Tourettes syndrome in children
c. When used as “anorectic “ in obese, make sure client is on a weight reduction program. Give 30 to 60 minutes before meals
d. Explain to client the reason, what to expect, and dangers of this drugs
e. Tell the client to avoid caffeine containing drinks
f. Warn the client to avoid activities that require alertness
h. Instruct client to take 6 hours before bedtime to avoid sleep interference
i. Inform client that as drug wears off, fatigue may result
COMMON CNS stimulants:
I. AMPHETAMINE SULFATE
ACTION – in children with hyperkinesia
CONTRAINDICATIONS
a. In clients with parkinsonism
b. Contraindicated within 14 days of MAO inhibitors
DRUG INTERACTIONS:
- ammonium chloride, ascorbic acid
- antacids, sodium bicarbonate, acetazolamide
- antihypertensives
- caffeine
- haloperidol, phenothiazine, tricyclic antidepressants
- insulin, oral antidiabetic
- ammonium chloride
- bicarbonate
NURSING MANAGEMENT:
a. be aware that high doses can result in acute psychotic picture
b. know that amphetamines are subject to abuse, that leads to compulsive behavior, paranoia, hallucinations and suicidal tendencies
c. be aware for the street names ( black beauties, lid poppers, pep pills and speed)
d. note that amphetamines should only be used in weight reduction programs for clients in whom alternate therapy has been ineffective
II. DEXTROAMPHETAMINE (DEXEDRINE)
- related both chemical and pharmacologic to norepinephrine
- peak occurs within 4 to 6 hours
- elimination half-life is about 5 hours
- metabolized in the liver and excreted in the urine
- drug interations: same as for amphetamine
- side/adverse effects: same as for amphetamine
III. METHAMPHETAMINE HYDROCHLORIDE ( DESOXYN)
- like dextroamphetamine related to norepinephrine. It is often referred to as “speed”
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- pharmacokinetics: same as for dextroamphetamine
- used with caution in clients with hypertension
IV. DIETHYLPROPION HYDROCHLORIDE (TENUATE)
- an anorexiant
- half-life 4 to 6 hrs; effects of regular-release tablets persist for 4 hours; effects of extended-release tablets and capsules can last for 12 hours
- short term adjunct in exogenous obesity
- suppressing the appetite
V. PHENTERMINE (IONAMINE)
- used along with Fenfluramine as diet aid; known as the “phen/fen diet”
- less potent action in the CNS than most amphetamines, with little stimulation of the CV system
- duration of action is prolonged and may last up to 20 hours.
ANALGESICS
A. OPIODS
- symptomatic relief of severe acute and chronic pain
- most commonly used in the postoperative setting and to treat pain caused by malignancy
- produce effects by binding to opioid receptors throughout the CNS and peripheral tissues
- onset of action is immediate if given by IV and rapid if given by IM or by mouth
- peak action is from 1 to 2 hours and duration up to 7 hours
- these agents cross the BBB and placental barriers and also into breast milk
- may increase intracranial pressure
- causes anorexia
NURSING CONSIDERATIONS:
1. assess pain for type, intensity and location
2. assess VS especially the RR (<12 bpm withhold)
3. assess for CNS changes including LOC
4. assess client for allergic reaction
5. assess older adults frequently
CLIENT EDUCATION:
1. avoid alcohol and other CNS depressants
2. not over the counter
3. avoid ambulation, smoking, driving and other activities without assistance
4. report any changes such as allergic reactions or shortness of breath
5. long-term use can lead to withdrawal symptoms with termination of use
COMMON OPIOID ANALGESICS:
Pure agonist – Codeine (Paveral)
- IM and PO
- Meperidine (Demerol)
- PO, IM, IV, SubQ
- Morphine Sulfate
- PO, IV
- sevre pain, short acting
Mixed agonists-antagonist
- Nalbuphine hydrochloride (Nubain)
- IM, IV, SubQ, IV
- limited use for severe and chronic pain
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b. OPIOID ANTAGONIST
- include Naloxone (Narcan) and Naltrexone (ReVia)
- used to reverse respiratory depression induced by overdose of opioids
- onset of effect 1-2 minutes, duration 45 minutes
NURSING CONSIDERATIONS:
1. assess VS q 3-5 minutes
2. assess ABG
3. assess cardiac status
4. assess RR and LOC
5. administer only with resuscitative device nearby
c. NON-OPIOIDS
1. ACETYLSALICYLIC ACID (ASPIRIN)
- inhibits prostaglandin involved in the production of inflammation, pain and fever
- blocks pain impulses in CNS
- antipyretic action results from vasodilatation of peripheral vessels
- inhibits platelet aggregation
- dosage varies depending on age of client
- gastric irritation may be decreased by administering with full glass of water, milk, food or antacid
- pills can be crushed or chewed but do not crush enteric-coated preparations
- give 30 minutes prior to or 2 hours following meals
- contraindicated in children < 12 y/o because of risk of Reye’s syndrome, children w/ chicken pox or flu-like symptoms, pregnacy 3rd trimester, lactation
- contraindicated with Vitamin K deficiency, PUD, anemia, renal and hepatic dysfunction
NURSING CONSIDERATIONS:
1. assess for allergy to salicylates
2. assess liver functions tests, renal function tests (BUN,Crea) and blood studies (CBC, Hct, Hgb, PT)
3. assess for hepatotoxicity
( dark urine, clay-colored stool, jaundice, itching)
4. note for abdominal pain, fever, diarrhea
5. evaluate for therapeutic responses
6. assess for aspirin toxicity when administered with ammonium chloride
CLIENT TEACHING:
1. report any symptoms of hepatotoxicity or renal toxicity
2. report visual changes, tinnitus, allergic reactions, and bleeding
3. take medication with 8 oz water, milk or food
4. do no exceed recommended dose
5. do not combine with other OTC medications containing ASA
6. therapeutic response can take up to 2 weeks
7. avoid alcohol ingestion to decrease chance of GI bleeding
8. should not be given to children or teens with flu-like symptoms or chicken pox
2. ACETAMINOPHEN (TYLENOL)
- inhibition to prostaglandin synthesis
- possess weak anti-inflammatory properties
- more on anti-pyretic action
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- used to mild to moderate pain or fever, especially when ASA or NSAIDs are not tolerated
- usual dose is 325 to 600 mg q4-6h PO or PR, maximum dose is 4 grams per day
- oral forms may crushed or given as whole or chewable tablets
- may give with food or milk to increase gastric tolerance
- co-administration with high-carbohydrate meal with significantly retard absorption rate
- hepatotoxicity
- cyanosis, anemia, neutropenia, jaundice, pancytopenia, CNS stimulation, delirium
NURSING CONSIDERATIONS:
1. assess client for chronic poisoning (rapid, weak pulse, dyspnea, cold, clammy extremities)
2. assess for hepatotoxicity
3. be prepared to administer ACETYLCYSTEINE (MUCOMYST) as antidote for acetaminophen poisoning
3. NONSTEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDs)
- inhibit cyclooxygenase and decrease prostaglandins and thromboxane
- used to treat mild to moderate pain, osteoarthritis and dysmenorrhea
- gastric irritants
- crushed or chewed (Pills only)
- give 30 minutes prior to or 2 hours following meals for best absorption
NURSING CONSIDERATIONS:
1. assess for renal and hepatic function
2. audiometric, ophthalmic exam before, during, and after treatment
3. assess for ear and eye problems
CLIENT EDUCATION:
1. report blurred vision, ringing, roaring in ears which may indicate toxicity
2. avoid driving or other hazardous activities
3. report changes in urine pattern, increased weight, edema, increased pain in joints, fever, blood in urine indicating nephrotoxicity
COMMON NSAIDs AGENTS:
1. Celecoxib (Celebrex)
- PO
- decreases effect of ASA, ACE inhibitors, diuretics
2. Diclofenac sodium (Voltaren)
- PO
3. Ibuprofen (Advil)
- PO
4. Ketorolac (Toradol)
- IV, IM, PO
5. Mefenamic Acid (Ponstan)
- PO
6. Naproxen (Naprosyn)
- PO
7. Piroxicam (Feldene)
- PO
ANTICONVULSANTS AGENT
- These agents include hydantoins, iminostillbenes, succinimides, valproic acid
- Suppress seizure activity by altering ionic conductance, neuronal membrane potentials and the level of certain neurotransmitters
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- Management and control of partial and generalized seizures that are idiopathic or unresponsive to other interventions
- There are no contraindications to anti-epileptic use
- teratogenecity: Fetal hydantoin syndrome has been associated with antiepileptic use in pregnancy (specifically phenytoin or other hydantoin drugs)
HYDANTOINS
- suppress sodium influx across neuronal cell membranes
- inhibit the spread of seizure activity in the motor cortex
- used in general toni-clonic (grand mal), status epilepticus, pyschomotor seizures (complex focal seizures)
- do not interchange chewable phenytoin products with capsules
- phenytoin readily binds with protein
- give ethosuximide, diazepam, and carbamazepine with food or milk to reduce GI symptoms
- significant food interactions: Phenytoin absorption is decreased by enteral nutrition products
- paresthesias, nystagmus, diplopia, gingival hyperplasia
- Steven-Johnson syndrome
NURSING CONSIDERATIONS:
1. assess for seizure activity including type, location, duration, and character
2. assess mental status, mood, sensorium, affect and memory
3. assess for respiratory depression, rate, depth and character
4. administer dose with food to reduce risk of GI upset
CLIENT EDUCATION:
1. medication regimen (name, dose, schedule, SE, and possible adverse effects)
2. urine may turn pink
3. do not discontinue abruptly or without consulting physician
4. brush teeth with soft toothbrush and do proper flossing to prevent gingival hyperplasia
5. avoid heavy used of alcohol
BARBITURATES
- decrease impulse transmission to the cerebral cortex
- used in all forms of epilepsy
- give oral dose on empty stomach
- administer IM injection into large muscle mass to prevent tissue sloughing
SUCCINIMIDES
- suppress Calcium influx into neurons, inceasing the electrical threshold and decreasing ability to generate an action potential
- used in absence seizures, partial and tonic-clonic
NURSING CONSIDERATIONS:
1. Monitor renal studies including UA, BUN and creatinine
2. Assess for eye problems
3. Monitor weight weekly
BENZODIAZEPINES
- enhance the inhibitory neurotransmitter GABA to decrease anxiety and as an adjunct for seizure activity
- give with food or milk
- IV injection should be given into large vein
- contraindicated in acute narrow angle glaucoma
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- contraindicated in children younger than 6 months
- do not give to clients w/ liver disease (clonazepam) or during lactation ( diazepam)
NURSING CONSIDERATIONS:
1. assess BP, pulse if systolic BP drops 20mmHg withhold then notify physician
2. assess hepatic and renal function
3. advice to use barrier contraceptives while taking this drugs
Other antiepileptics:
1. CARBAMAZEPINE (TEGRETOL)
- inhibits nerve impulse by limiting influx of sodium ions across cell membrane in motor cortex
- used in tonic-clonic, complex partial and mixed seizures
- give oral forms with food and milk
- contraindicated with bone marrow depression
2. VALPROATES
- increases levels of GABA in brain, which decreases seizure activity
- given by the oral or enteral (GI tube) route
ANTIPYSCHOTICS
A. PHENOTHIAZINES
- neuroleptics
- also known as typical antipsychotic agents
- predominantly dopamine antagonists thus they block postsynaptic dopamine2 receptors in several DA in the brain
- typical antipsychotics are most effective in treating the “positive” symptoms but are less effective in the “negative” symptoms
- tolerance to antipsychotic medications is very uncommon
- most toxic drugs used in psychiatry
a. CHLORPROMAZINE (THORAZINE)
- used primarily to treat psychotic disorders
- 3 goals:
1. suppression of acute episodes
2. prevention of acute exacerbations
3. maintenance of the highest possible level of functioning
- effects can usually be seen in 1-2 days but substantial improvement usually takes 2-4 weeks and full effects into months
AUTONOMIC NERVOUS SYSTEM
CHOLINERGIC DRUGS
These drugs promote the action of neurotransmitter acetylcholine
Also called parasympathomimetic drugs ( because they produce effects that imitate parasympathetic nerve stimulation
Two major classes of cholinergic drugs:
a. cholinergic agonist – mimic the action of the neurotransmitter acetylcholine
b. anticholinesterase drugs – work by inhibiting the destruction of acetylcholine at cholinergic receptor sites
How cholinergic drugs work..
Cholinergic agonist
When a neuron in the PNS is stimulated, the neurotransmitter Ach is released. Ach crosses the synapse and interacts with receptors in the adjacent neuron. Cholinergic agonist drugs work by stimulating cholinergic receptors, mimicking the action of Ach.
Anticholinesterase drugs
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After Ach stimulates the cholinergic receptor, it’s destroyed by the enzyme acetylcholinesterase. Anticholinesterase drugs produce their effects by inhibiting acetylcholinesterase. As a result, Ach isn’t broken down and begins to accumulate; therefore, the effects of Ach are prolonged.
CHOLINERGIC AGONIST
Directly stimulating cholinergic receptors, cholinergic agonists mimic the action of the neurotransmitter acetylcholine
Example:
Acetylcholine Cevimeline
Pilocarpine Pilocarpine
Betanechol
Carbachol
Pharmacokinetics
- Depend on the affinity of the individual drug for muscarinic or nicotinic receptors
- For example, the drug acetylcholine poorly penetrates the CNS
- Usually administered: topically, with eye drops
orally
subcutaneous injection
( more rapidly than oral)
- Rarely administered by IM or IV
( because they’re almost immediately broken down by cholinesterase in the interstitial spaces between tissues and inside the blood vessels)
( begin to work rapidly and can cause cholinergic crisis)
- Cholinergic agonist are absorbed rapidly and reach peak levels within 2 hours
- Food decreases their absorption
- Less than 20% is protein bound
Summed up:
- All cholinergic agonist are metabolize by cholinesterase:
1. at the muscarinic and nicotinic receptor sites
2. in the plasma ( the liquid portion of the blood)
3. in the liver
- Excreted by the kidneys
Pharmacodynamics
- Works by mimicking the action of acetylcholine on the neurons in certain organs of the body called the target organs
- They stimulate the muscle and produce:
salivationbradycardia
dilation of BV constriction of pulmonary
increase GI tract increased tone & contraction
of the bladder
constriction of the pupils
Pharmacotherapeutics
- Treat atonic (weak) bladder conditions and postoperative and postpartum urine retention
- Treat GI disorders, such as postoperative abdominal distention and GI atony
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- Reduce eye pressure in patients with glaucoma and during eye surgery
- Treat salivary gland hypofunction
Drug interactions
- Other cholinergic drugs, especially anticholinesterase drugs (ambenopium, edrophonium, neostigmine) boost the effects of cholinergic agonist and increase the risk of toxicity
- Anticholinergic drugs
- Quinidine reduces the effectiveness of cholinergic agomist
Assessment:
1. Assess for disorders in which cholinergic agonist are used such as Myasthenia gravis
2. Assess for urine retention and bladder distention; determine the patients fluid intake , time and amount of last urination
3. Assess for possible paralytic ileus ( check for bowel sounds, abdominal distention and determine the patients elimination pattern)
4. Assess for disorders that may be aggravated by cholinergic agonist (Alzheimers dse.)
Implementation:
1. Administer cholinergic drugs as prescribed
2. Be aware that some drugs, such as Bethanechol should be given before meals
3. Monitor for effects of cholinergic drugs and report adverse reactions( nausea, vomiting, cramps, diarrhea, blurring of vision)
4. Assess for respiratory adequacy
5. Assess for urinary adequacy and signs of urine retention
Health teachings:
1. Take the drug as directed on a regular schedule to maintain consistent blood levels of the drug and symptom control
2. Don’t chew or crush sustained-release tablets or capsules
3. Take oral cholinergics on an empty stomach
4. If diarrhea or vomiting occurs, ensure adequate fluid intake
5. Cholinergic drugs act within 60 minutes. Make sure bathroom facilities are available.
6. If taking in long term mode, wear or carry medical alert identification
7. For those with MG, plan rest periods between activities and space activities throughout the day
8. Report increased muscle weakness, difficulty breathing, recurrence of MG symptoms
Anticholinesterase drugs
Block the action of the enzyme acetylcholinesterase at cholinergic receptor site
Preventing the breakdown of the neurotransmitter acetylcholine
As Ach builds up, it continues to stimulate the cholinergic receptors
Divided into 2 categories: Reversible and Irreversible
Reversible (short acting)
Ambenonium
Donepezil
Edrophonium
Neostigmine
Physostigmine
Rivastigmine
Tacrine
Irreversible (long acting)
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Used primarily as toxic insecticides and pesticides or as nerve gas agents in chemical warfare
Echothiopate
Pharmacokinetics
- Readily absorbed from the GI tract, subcutaneaous tissue and mucous membrane
- Because neostigmine is poorly absorbed from the GI tract, the patient needs a higher dose when taking this drug orally
- When a rapid effect is needed, the drug should be given in IM or IV route
- Distribution varies
- example: Physostigmine – cross the BBB
Donepezil – highly bound to plasma
CHON
Tacrine – about 55% bound
Rivastigmine – 40% bound
Galantamine – 18% bound
- Metabolized in the body by enzymes in the plasma and excreted in the urine
- Donepezil, Galantamine, Rivastigmine, and Tacrine are metabolized in the liver but still excreted in urine
Pharmacodynamics
- Promote the action of acetylcholine receptor sites
- They can produce a stimulant or depressant effect on cholinergic receptors
- Reversible – block the breakdown of acetylcholine for minutes to hours
- Irreversible – can last for days or weeks
Pharmacotherapeutics
1. To reduce eye pressure
2. To increase bladder tone
3. To improve tone and peristalsis through the GI tract in patients with reduced motility and paralytic ileus
4. To promote muscular contraction in patients with MG
5. To diagnosed MG
6. As antidotes to anticholenergic drugs, tricyclic antidepressants
7. To treat mild to moderate dementia and enhance cognition in patients with Alzheimers dse.
Drug Interactions
- Other cholinergic agonist, particularly cholinergic agonist ( bethanechol, carbachol, pilocarpine)
- Carbamazepine, dexamethasone, rifampicin, phenytoin and phenobarbital
- Aminoglycosides antibiotics, anesthetics and anticholinergic drugs
- Inhibitors of cytochrome P450 ( cimetidine and erythromycin)
- Cigarette used
Adverse Reactions
- Increased action of Ach at receptor sites
- Cardiac arrhythmias, nausea and vomiting, diarrhea, SOB, wheezing, seizures, headache, anorexia, insomnia, pruritus, urinary frequency and nocturia
Assessment:
1. Assess for disorders in which anticholinesterase drugs are used, such as MG, alzheimers, glaucoma and altered bladder function
2. Assess for urine retention and bladder distention, determine the patient’s fluid intake,
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and find out the time and amount of his last urination
3. Assess for possible paralytic ileus by checking for BS and abdominal distention and determining the patients elimination pattern
Anticholinergic drugs
- Interrupt parasympathetic nerve impulses in the CNS and ANS
- Prevent Ach from stimulating cholinergic receptors
- Don’t block all cholinergic receptors, just the muscarinic receptors sites
Belladonna Alkaloids
- Atropine
- Belladona
- Homatropine
- Hyocyamine
- Scopolamine
Synthetic derivatives of belladonna alkaloids
(quarternary ammonium drugs)
- Glycopyrrolate
- Methscopolamine
- Propantheline
Tertiary amines – newer synthetic drugs
- Centrally acting and more selective
- Fewer side effects
- Benztropine, Dicyclomine, Oxybutynin, Tolterodine, Trihexyphenidyl
Pharmacokinetics
- Belladonna alkaloids are absorbed from the eyes, GI tract, mucous membranes, and skin
- Quarternary ammonium drugs and tertiary amines are absorbed primarily through the GIT
- Belladona class are distributed more widely throughout the body
- Alkaloids readily cross the BBB
- Belladonna metabolized in the liver and excreted in the kidneys
- Metabolism of tertiary amines is unknown, but excretion is usually through the kidneys and feces
- Quarternary ammonium drugs are bit more complicated, hydrolysis occurs in the GIT and liver, excretion is n feces and urine
Pharmacodynamics
- Produces paradoxical effect (depending on the dosage, condition being treated and target oragn)
- Example: in the brain they can produce a stimulating and depressing effect
- Example: Parkinson’s dse, characterized by low dopamine levels that intensify the stimulating effects of Ach, cholinergic blcokers depress this effect
Pharmacotherapeutics
- anticholinergic drugs are used in various GI situations
1. all anticholinergic drugs are used to treat spastic or hyperactive conditions of the GI and urinary tracts
- for bladder relaxation and urinary incontinence, quarternary ammonium compounds (propantheline) drug of choice because of fewer adverse effects
2. the belladonna alkaloids are used with morphine to treat biliary colic
3. given by injection before some diagnostic procedures to relax the GI smooth muscles
Drug Interactions
- Drugs that increase the effects of anticholinergic drugs include:
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1. antidyskinetics ( amantadine)
2. antiemetics and antivertigo drugs ( meclizine)
3. antipsychotics (haloperidol)
4. cyclobenzaprine
5. tricyclic and tetracyclic antidepressants
Adverse Reactions
- Dry mouth, reduced bronchial secretions, increased heart rate, blurred vision, decreased sweating
Assessment
- Assess for conditions in which anticholinergic drugs would be used, such as bradycardia, heart block, diarrhea and PUD
- Assess for conditions in which anticholinergic drugs would be contraindicated ( glaucoma, MG, prostatic hyperplasia, reflux esophagitis, GI obstructive dse)
Implementation
1. Follow dosage recommendations, some drugs should be given with meal
2. Monitor VS, cardiac rhythm, UO, and vision for potential drug toxicity
3. Monitor for adverse reactions (dry mouth, inc heart rate and blurred vision)
Adrenergic drugs
- Also called sympathomimetic drugs
- Classified into two groups based on their chemical structure: cathecolamines and noncatecholamines
- Also divided by action:
1. direct acting – acts directly on the organ or tissue innervated by SNS
2. indirect acting – in which the drug triggers the release of neurotransmitters (norepinephrine)
3. dual acting - both
Catecholamines
- They stimulate the nervous system, constrict peripheral blood vessels, increase heart rate and dilate the bronchi
- Common examples:
dobutamine dopamineepinephrine
norepinephrine
isoproterenol Hcl/sulfate
Pharmacokinetics
- can’t be take orally (destroyed by digestive enzymes)
- In contrast, when these drugs are given sublingually, rapidly absorbed though the mucous membrane
- SC absorption is slowed ( cause the BV around the injection site to constrict)
- IM faster because of less constriction
- Metabolized and inactivated predominantly in the liver ( GIT, lungs, kidneys, plasma, tissues)
- Excreted primarily in the urine ( isoproterenol – feces, epinephrine – breast milk)
Pharmacodynamics
- Primarily direct acting
- Combine with alpha-adrenergic or beta-adrenergic receptors
- Cause either excitatory and inhibitory
- Alpha-adrenergic – excitatory response except for intestinal relaxation
- Beta-adrenergic – inhibitory except in the cells of the heart
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Pharmacotherapeutics
- Most adrenergics produce their effects by stimulating alpha and beta adrenergic receptors
- Norepinephrine has the most nearly pure alpha activity
- Dobutamine and isoproterenol have only beta therapeutic use
- Epinephrine stimulates alpha and beta
- Dopamine primarily exhibits dopaminergic activity
- Cathecholamines that stimulate alpha-adrenergic are used to treat hypotension ( loss of vasomotor tone, blood loss
- Cathecolamines that stimulate beta1-adrenergic are used to treat bradycardia, heart block, low cardiac output, ventricular fibrillation, asystole, cardiac arrest
- Cathecolamines that exert beta2-adrenergic activity are used to: acute and chronic bronchial asthma, emphysema, bronchitis, acute hypersensitivity
- Dopamine is used in low doses to improve blood flow to the kidneys (it dilates the renal blood vessels)
Drug Interactions:
Alpha-adrenergic blockers (phentolamine) – can produce hypotension
Epinephrine – may cause hyperglycemia
Beta-adrenergic blockers (propanolol) – can lead to brochial constriction
Tricyclic antidepressants – can lead to hypertension
Adverse reactions:
- Palpitations
- Cardiac arrhtyhmias
- Hypotension
- Hypertension and hypertensive crisis
- Increased glucose levels
- Tissue necrosis and sloughing
Assessment:
1. Assess the pt.’s condition before tx
2. Continuously monitor ECG, BP, PAWP, cardiac condition, UO
3. Monitor electrolyte levels
4. After dopamine is stopped, watch closely for a sudden drop in BP
Implementation:
1. Before starting catecholamines, correct hypovolemia with plasma volume expanders
2. Give cardiac glycosides before cathecolamines; cardiac glycosides increase AV node conductions and patients with AF may develop rapid ventricular rate
3. Administer drug using central venous catheter or large peripheral vein
4. Dilute the concentrate for injection before administration
5. Watch for irritation and infiltration; extravasation can cause an inflammatory response
6. Don’t give cathecolamines in the same IV line as other drugs (beware of incompatibilities)
ex. Dobutamine – heparin, hydrocortisone sodium
succinate, cefasolin, penicillin
7. Don’t mix dobutamine or dopamine with sodium bicarbonate injection or phenytoin ( incompatible with alkaline solutions)
8. Change IV sites regularly to avoid phlebitis
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9. Provide patient teaching
Noncathecolamines
- Many therapeutic uses because of the various effects these drugs can have on the body including:
1. local and systemic constriction of blood vessels (phenylephrine)
2. nasal and eye decongestion and dilation of the bronchioles ( albuterol, bitolterol, ephedrine, formoterol, isoetharine Hcl, terbutaline)
3. smooth muscle relaxation (terbutaline)
Pharmacokinetics:
- Depends on the route of administration
1. inhaled drugs (albuterol) – gradually absorbed from the bronchi thus resulting in lower drug levels in the body
2. oral drugs – absorbed well from the GI tract and are distributed widely in the body fluids and tissues
3. some crosses the BBB (ephedrine)
- Metabolism and inactivation of noncathecolamines occur primarily in the liver but also in the lungs, GIT and other tissues
- Excreted primarily in the urine
- Inhaled albuterol are excreted within 24 hours
- Oral albuterol – within 3 days
- Acidic urine increases excretion of many noncathecolamines, alkaline urine slows excretion
Pharmacodynamics:
- Noncathecolamines can be direct-acting, indirect or dual ( unlike cathecolamines, primarily direct-acting)
1. direct-acting noncathecolamines – stimulate alpha activity receptors including phenylephrine. Those that selectively stimulate
beta2 activity receptors (albuterol, isoetharine, metaproterenol, terbutaline)
2. indirect-acting noncathecolamines – exert their effect by indirect action on adrenergic receptors
3. dual acting – ephedrine and mephentermine
Pharmacotherapeutics:
- Stimulate SNS and produce various effects on the body
1. mephentermine – causes vasoconstriction and is used to treat hypotension in severe shock
2. terbutaline – used to stop in preterm labor
Drug interactions:
- Anesthetics – can cause arrthymias and hypotension
- Monoamine oxidase inhibitors – severe hypertension
- Tricyclic antidepressants – cause hypertension and arrthymias
- Urine alkalizers ( acetazolamide and Na bicarb) – can cause slow excretion
Assessment:
- Obtain a baseline assessment of the pt’s respiratoty status, and assess it frequently throughtout therapy
- Assess for adverse reactions and drug interactions
- Assess the pt’s and family’s knowledge of the drug therapy
Adrenergic blocking drugs
- Also called sympatholytic drugs
- Used to disrupt SNS
- Their action at these sites can be exerted by:
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1. interrupting the action of adrenergic drugs
2. reducing available NE
3. preventing the action of cholinergic drugs
- Classified according to their site of action as:
1. alpha-adrenergic blockers (alpha blockers)
2. beta-adrenergic blockers ( beta blockers)
Alpha-adrenergic blockers
- Work by interrupting the actions of the cathecolamines ( E and NE) at alpha receptors
- This results in:
1. relaxation of the smooth muscle in the blood vessels
2. decreased blood pressure
- Drugs in this class includes:
ergoloid mesylates ergotamine
phenoxybenzamine phentolamine
terazosindoxazosin
prazosin
Pharmacotherapeutics:
- Hypertension
- Peripheral vascular disorder
- Pheochromocytoma
- Vascular headache
Implementation:
1. Give drugs at bedtime
2. Begin tx with small dose to avoid syncope
3. Don’t give sublingual tablets with food or drink
4. Provide patient teaching
Beta-adrenergic blockers
- Most widely used adrenergic blockers
- Prevent stimulation of the SNS by inhibiting the action of cathecolamines at beta adrenergic receptors
- Beta-adrenergic blockers are selective or nonselective beta-adrenergic blockers affect:
1. beta1 receptors site (heart)
2. beta2 receptor site (bronchi, BV and uterus)
Nonselective:
*Carvedilol
*Labetalol
- Levobunolol
- Penbutolol
- Pindolol
- Propanolol
* Also block alpha1 receptors
Selective:
- Acebutolol
- Atenolol
- Betaxolol
- Bisoprolol
- Esmolol
- metoprolol
Pharmacokinetics:
- Usually absorbed rapidly from the GIT
- Protein bound to some extent
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- Distributed widely in body tissues, with the highest concentrations found in the heart, liver, lungs and saliva
- Nadolol and atenolol – urine, feces and breastmilk
- Metabolized in the liver
Pharmacotherapeutics:
- Can be prescribed after a heart attack to prevent another heart attack or to treat:
1. angina
2. hypertension
3. hypertrophic cardiomyopathy
4. SV arrhythmias
Assessment:
- Assess respiratory status (COPD or asthma because of potential vasospasm)
- Check apical pulse rate ( alert the prescriber if pulse rate is below 60bpm)
- Monitor BP, ECG, HRR ( be alert for progression of AV block or bradycardia)
Nursing Pharmacology
Anti- Neoplastic
Chemotherapeutic Drugs
General Description
These agents kill or inhibit the reproduction of neoplastic cells
They may be cycle specific or non specific
They are used in combination, or with other treatment modalities
Usull given IV
Undesirable effects
“BARFS”
Bone Marrow Depression
Alopecia
Retching- Nausea and Vomiting
Fear and Anxiety
Stomatitis
General Guidelines for Anti-Neoplastic Agents
CBC and Platelets monitoring
Anti-emetics are given BEFORE drug
NEPHROTOXICITY is an important Side effect
Counseling regarding reproductive issues
Encourage hand washing and avoidance of crowds
Recommend wig for alopecia
General guidelines
General Types
ALKYLATING agents
ANTI METABOLITES
ANTIBIOTICS
MITOTIC INHIBITORS
HORMONAL agents
IMMUNOSUPPRESANTS
Alkylating Agents
DYNAMICS: cause cell death or mutation
INDICATIONS: Palliative treatment of chronic lymphocytic leukemia, malignant lymphomas, Hodgkin’s disease, cancers of the breast, lungs and ovaries
ADVERSE EFFECTS: Bone marrow depression, anorexia, alopecia, N/V
Alkylating Agents
Busulfan
Carboplatin
Carmustine
Chlorambucil
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Cisplatin
Cyclophosphamide
Ifosphamide
Mecholethamine
Alkylating Agents
Nursing Interventions
Monitor CBC weekly
Hydrate patient well
Pre-medicate with anti-emetics
Monitor IV site
Prepare epi, steroids and antiH1
Drug Specific Side effects
ANTI-METABOLITE
DYNAMICS: interferes with the building block of DNA synthesis
INDICATIONS: Myelocytic leukemia, acute lymphocytic leukemia, cancers of breast, cervix, colon, liver, ovaries
ADVERSE EFFECTS: GI disturbance, oral and anal inflammation, bone marrow depression, alopecia, renal dysfunction and thrombocytopenia
General Guidelines for anti-metabolites
Monitor CBC and Platelets weekly
Evaluate renal functions
Take temperature Q 4 hours
Aseptic techniques
Bleeding, anemia, infection and nausea
Oral hygiene
Lots of fluids (2-3 liters/day)
Intake and output, nutrition
The protocols for handling- follow them
Emphasize protective isolation
Anti-metabolites
Capecitabine
Cytarabine
Fluouracil
Methotrexate
Mercaptopurine
Thioguanine
Floxuridine
Anti-Metabolites
Nursing Interventions
Evaluate complete blood count
Pre-medicate with anti-emetics
Safety measures for dizziness
Instruct to report fever, sore throat, rash and bleeding
Provide small, frequent feedings
Suncreens for photosensitivity
Anti-Metabolites
Nursing Interventions
When administering methotrexate, prepare to administer leucovorin (folinic acid or citrovorum factor) to prevent toxicity
Anti-Neoplastic Antibiotics
DYNAMICS: these kill cancer cells by disrupting the DNA synthesis and breaking up the DNA linkages
INDICATIONS: Leukemia, carcinomas, adenocarcinoma
ADVERSE EFFECTS: bone marrow suppression, alopecia, NAVD, renal toxcity
Anti-Neoplastic Antibiotics
Bleomycin
Dactinomycin
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Daunorubicin
Doxorubicin
Idarubicin
Mitocycin
Plicamycin
Anti-Neoplastic Antibiotics
Daunorubicinà CHF and Dysrhythmia
Doxorubicinà Cardiotoxicity
Bleomycinà pulmonary toxicity
Plicamycinà excessive bleeding
Anti-Neoplastic Antibiotics
NURSING INTERVENTIONS
Monitor blood tests, cardiac functions
Ensure that the patient is well-hydrated
Provide small, frequent feedings
Advise wig for alopecia
Instruct to maintain oral hygiene
Assess the ECG frequently
MITOTIC INHIBITORS
DYNAMICS: kill the cells as the process of Mitosis begins by blocking the mitotic spindles causing cell death
INDICATIONS: Combination therapy for reproductive cancer, cancers of the lungs, Lymphomas
ADVERSE EFFECTS: bone marrow suppression, NAVD, renal and hepatic toxicity , alopecia
MITOTIC INHIBITORS
Etoposide
Teniposide
Vinblastine
Vincristine (Oncovin)
Vinorelbine
MITOTIC INHIBITORS
Vincristine (Oncovin)
Can cause NEUROTOXICITY
Cause severe bone depressionà check CBC
MITOTIC INHIBITORS
NURSING INTERVENTIONS
Arrange for blood tests
Avoid direct skin and eye contact with drugs
Ensure hydration
Small, frequent meals
Wig
Anti-emetics
Hormone and Immunomodulators
DYNAMICS: receptor-site specific drugs that block the specific hormones in the cancer
INDICATIONS: Breast cancer, prostate cancer
ADVERSE EFFECTS: menopause associated effects like hot flashes, vaginal dryness. Bone marrow depression and HYPERCALCEMIA
Hormone and Immunomodulators
Tamoxifen à anti-estrogen
Anastrazole
Estramustine
Letrozole
Testolactone
Toremifene
Goserelinà GnRH analogue
Flutamide
Fluoxymesteroneà an ANDROGEN
Diethylstilbestrol (DES)à estrogen preparation
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Hormone and Immunomodulators
NURSING INTERVENTIONS
Arrange for blood tests to monitor bone marrow depression
Provide small, frequent meals
Advise comfort measures for menopausal symptoms
Utilize BARRIER methods of contraception
Miscellaneous
L-Asparaginase
Enzyme that destroys ASPARAGINE needed by malignant cells for protein synthesis
Indicated for acute lymphocytic leukemia
Adverse effects: PANCREATITIS, bone marrow depression, fatal hyperthermia, hypersensitivity
Miscellaneous
Azathioprine
Used as adjunct to cyclosporine and steroids to suppress immune system
CAN CAUSE bone marrow suppression and increase incidence of cancers
Taken with meals
Avoid crowds, maintain hygeine
Anti-emetics
Metoclopromide
Odansetron
Dronabinol
In Summary
Cancers arise from a single abnormal cell that multiplies and grows
Cancers can come from epithelia cells- CARCINOMA or mesenchymal cells- SARCOMA
Cancer cells lose their normal functions and they grow uninhibited
In Summary
Anti-neoplastic agents affects both the normal cells and the cancers cells
They act by disrupting cell function and division
Most cancer drugs are MOST effective against cancer cells that multiply RAPIDLY
In Summary
The ULTIMATE GOAL of cancer therapy is to decrease the size of the cancer so that the body’s immune system can eliminate the cancer
Anti-cancer drugs are BEST given in combination so as to affect the cancer cells in various stages
In Summary
ADVERSE effects commonly encountered with cancer therapy are related to damage to RAPIDLY multiplying cells like the BONE MARROW, hair follicle and Gastro-intestinal lining
In Summary
In general, these drugs SHOULD NOT be used during pregnancy or lactation because they may cause serious adverse effects on the FETUS
Hematologic Drugs
Hematologic drugs
There are numerous agents utilized to maintain, preserve and restore circulation. The three important dysfunction of blood are thrombosis, bleeding and anemia are commonly treated with various agents. The common ones that nurses must REVIEW are the:
Anticoagulants
Antilipemics
Antiplatelets (antithombotics)
Thrombolytics
Anti-anemics or Hematinics
Drugs to treat bleeding
The Anti-Coagulants
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The anticoagulants interfere with the coagulation process by interfering with the clotting cascade and thrombin formation. These agents are used to inhibit clot formation, but they do NOT dissolve existing clots.
The Anticoagulants commonly used are:
Heparin
Warfarin (Coumadin)
Dicumarol
Anisindione (Miradon)
Heparins
These are anticoagulants given orally or parenterally- SQ and IV.
Heparin is naturally found in the human liver that normally prevents clot formation.
Heparin is strongly acidic because of the presence of sulfate and carboxylic acid groups in the heparin chain.
Heparin
The mechanism of action of Heparin
Heparin (Liquamen Sodium) acts prophylactically to prevent the formation of blood clots in the vasculature.
It combines with ANTITHROMBIN III, a substance in our blood sometimes called heparin factor that inactivates THROMBIN.
By inhibiting the action of thrombin, conversion of fibrinogen to fibrin does not occur and the formation of a fibrin clot is prevented.
Heparins
Clinical Indications of Heparins
deep vein thrombosis
pulmonary embolism
coronary thrombosis,
patients with artificial heart valves and stroke patients
Heparins
Contraindications of heparin
Anticoagulants are not given to patients with bleeding disorders, peptic ulcers and patients who underwent recent eye/brain/spinal surgery.
It is NOT given to patients with severe liver and renal disease, hemophilia, and CVA.
Heparin is a large protein molecule that cannot pass through the placenta easily and can be given to pregnant women.
Heparins
Pharmacokinetics: the Adverse Effects of Heparin
INCREASES the clotting time and also DECREASES the platelet count. In this regard, monitoring of the aPTT/PTT (N= 20-30 seconds) and platelet count is required.
Hematologic effects: increased bleeding, thrombocytopenia
Skin-itching and burning
Hypersensitivity reactions like chills, fever, urticaria or anaphylaxis can occur since heparin is obtained from animal sources.
Life threatening adverse effect is Hemorrhage
Heparins
The Nursing process and Heparin
Assessment
Patient history
Physical examination- the nurse obtains baseline vital signs and physical assessment.
She must obtain laboratory results of the complete blood count, platelet count and activated partial thromboplastin time (aPTT), and clotting time.
Heparins
IMPLEMENTATION:
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Monitor the aPTT closely (it should be 1.5-2.5 times normal value)
Monitor vital signs and hematological status regularly.
Monitor signs of bleeding- hematuria, epistaxis, ecchymoses, Hypotension and occult blood in stool
Have available ANTIDOTE for heparin- PROTAMIME SULFATE
Heparins
IMPLEMENTATION:
Instruct the client not to use any over the counter drug without notifying the physician
Administer heparin subcutaneously in the abdominal region, using a 25-28-gauge needle at a 90-degree angle. DO NOT MASSAGE OR RUB THE AREA as this may cause bruising.
Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes.
Provide gently skin and oral care.
Heparins
Evaluation
Monitor the effectiveness of the medication:
Decreased formation of clot
PTT is 2x the normal
The Oral Anticoagulants
There are three commonly used oral anticoagulant agents in the hospital
Warfarin- most commonly used, synthesized from dicumarol
Dicumarol
Anisindone
The Oral Anticoagulants
Pharmacodynamics: the mechanism of Action of the Oral agents
These agents INHIBIT the liver synthesis of the Vitamin K clotting factors – factors II, VII, IX, and X.
The Oral Anticoagulants
Clinical indications of oral anticoagulants
These drugs are used to prevent blood clotting in patients with thrombophlebitis
pulmonary embolism and embolism from atrial fibrillation.
Because Warfarin crosses the placental barrier, it is NOT given to pregnant mothers.
The Oral Anticoagulants
Contraindications and precautions
Oral anti-coagulants are NOT given to patients with bleeding disorders, peptic ulcers, severe renal/liver diseases, hemophilia, CVA blood dyscrasias and eclampsia.
It is NOT given to pregnant mothers because it is teratogenic and can cause abortion
The Oral Anticoagulants
Pharmacokinetics:
Oral anticoagulants prolong the clotting time and are monitored by the Prothrombine Time (PT- average of 9-12 seconds). This is usually performed before administering the next dose. The PT level should be 1.5-2 times the reference value to be therapeutic.
The normal INR is 1-2. If the patient is on oral anticoagulant therapy, the INR is maintained at an INR of 2.0-3.0. If the INR is below the recommended range, warfarin is increased. If it is above the recommended range, warfarin should be reduced.
The Oral Anticoagulants
Pharmacokinetics: the Adverse Effects of Warfarin
Hematologic effects: increased bleeding, thrombocytopenia
Anorexia, nausea, vomiting, diarrhea, abdominal cramps, rash and fever.
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Alopecia, bone marrow depression, and dermatitis.
Life threatening adverse effect is Hemorrhage
The Oral Anticoagulants
The Nursing process and Warfarin
Assessment
Patient history-. The nurse determines the current medications taken, PREGNANCY, and history of recent surgery.
Physical examination- the nurse obtains baseline vital signs and physical assessment.
laboratory results of the complete blood count, platelet count and Prothrombin time, INR and clotting time.
The Oral Anticoagulants
Implementation
Monitor vital signs and hematological status
Monitor signs of bleeding- hematuria, epistaxis, black tarry stools, echymoses, Hypotension and occult blood in stool
Have available ANTIDOTE for warfarin- VITAMIN K or phytonadione.
The Oral Anticoagulants
Implementation
Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes. Provide gently skin and oral care.
Instruct the patient to avoid foods high in vitamin K like spinach, nuts
The Oral Anticoagulants
Evaluation
Monitor the effectiveness of the medication
Decreased formation of blood clots
Check the PT and INR
Should be 2x the normal
Anti-platelets
These are agents decrease the formation of the platelet plug by decreasing the responsiveness of the platelets to various stimuli that would cause them to stick and combine together on a vessel wall
Aspirin
Dipyridamole
Sulfinpyrazone
Ticlopidine
Clopidogrel
Glycoprotein receptor antagonists
Abciximab
Eptifibatide
Tirofiban
Anti-platelets
The mechanism of action of platelet inhibitors
These agents INHIBIT the aggregation of platelets in the clotting process by blocking receptor sites on the platelet membrane, preventing platelet-to-platelet interaction, thereby prolonging the bleeding time.
Anti-platelets
Clinical indications
Prevention of myocardial infarction and stroke
Prevention of a repeat myocardial infarction
Prevention of stroke for those with transient ischemic attack
In patients with graft to maintain its patency.
Anti-platelets
Pharmacodynamics: the adverse effects of Antiplatelets
Bleeding is the most common side effect
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GIT- gum bleeding, gastric bleeding, tarry stools
CNS- headache, dizziness and weakness
Skin- petechiae, bruising, allergy
ASPIRIN toxicity: tinnitus
Anti-platelets
Nursing considerations
Determine if the patient is allergic or sensitive to the medications
Monitor closely the vital signs and bleeding areas
Instruct the patient to take drug with food
Monitor the bleeding time, clotting time and platelet count
Anti-platelets
Nursing considerations
Suggest safety measures including the use of an electric razor and avoidance of contact sports.
Provide increased precautions against bleeding during invasive procedures.
Use pressure dressings and ice to decrease excessive blood loss.
Monitor for tinnitus
The Thrombolytics
These thrombolytic agents are used to activate the natural anticlotting fibrinolytic mechanism to convert plasminogen to plasmin, which destroys and breaks down the fibrin threads in the blood clot (FIBRINOLYSIS). The result is clot disintegration.
The commonly used thrombolytics “---ase”
Streptokinase
Urokinase
Tissue plasminogen activator (t-PA) or alteplase
Anistreplase
Reteplase
The Thrombolytics
The mechanisms of actions of each agent
Streptokinase and urokinase are ENZYMES that act SYSTEMICALLY to dissolve the blood clots by activating plasminogen to plasmin.
The Thrombolytics
Clinical indications of thrombolytics
Myocardial infarction
Pulmonary embolism
Thromboemboilic stroke
Peripheral arterial thrombosis and
to open clotted IV catheters.
The Thrombolytics
Pharmacokinetics: The adverse effects of Streptokinase
CVS- Hypotension and dysrhythmias (usually upon reperfusion of the heart)
Hematological: increased bleeding- the most common effect.
Headache, nausea, flush, rash and fever
Allergic reaction- especially steptokinase and urokinase
Major adverse effect- hemorrhage.
The Thrombolytics
Implementation.
Monitor signs of active bleeding from mouth and rectum bleeding- hematuria, epistaxis, echymoses
Have available ANTIDOTE for thrombolytics: AMINOCAPROIC ACID!
Have available blood for emergency use.
Advise patient not to smoke, use electric razors to shave, use soft toothbrush and control sudden hemorrhage by direct pressure for 5-10 minutes.
Provide gently skin and oral care. As much as possible, avoid frequent venipuncture.
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The Thrombolytics
Evaluation
Monitor the effectiveness of the medication
Clot lysis
The Agents to treat bleeding
Aminocaproic acid and tranexamic acid
These are fibrin stabilizers that maintain or stabilize the clot in the bleeding vessels
The Agents to treat bleeding
Protamine sulfate
This agent antagonizes the anticoagulant effects of heparin. It is derived from fish testis and is high in arginine content.
The positive charge interacts with the negative charge of heparin to forma stable inactive complex.
The Agents to treat bleeding
Vitamin K
Vitamin K is given to antagonize the effects of the oral anticoagulants.
The response to Vitamin K is slow, requiring about 24 hours
thus, if immediate hemostasis or bleeding control is required, fresh frozen plasma should be ordered by the physician.
Antihyperlipidemics
These drugs target the problem of elevated serum lipids
Resins and bile acid sequestrants
Cholestyramine
Colestipol
Fibric Acid Derivatives
Clofibrate
Gemfibrozil
Fenofibrate
HMG CoA reductase inhibitors= “statins”
Atorvastatin
Cerivastatin
Fluvastatin
Lovastatin
Pravastatin
Simvastatin
Nicotinic acid
Probucol
statins
Pharmacodynamics: The mechanism of action of the Statins
These agents INHIBIT the enzyme HMG CoA reductase in the synthesis of cholesterol.
By inhibiting the important enzyme in cholesterol production in the liver, the statins decrease the plasma concentration of cholesterol and lower the LDL level with slight increase in the HDL level.
statins
Therapeutic indications
These agents are given to patients with CORONAY ARTERY DISEASE and hyperlipidemia, hypercholesterolemia
These statins are very effective in all types of hyperlipidemias.
The antianemics: Iron preparations and Epoetin
Iron preparations
Iron is important for hemoglobin formation.
The iron preparations are:
Ferrous sulfate
Ferrous fumarate
Ferrous gluconate
The antianemics: Iron preparations and Epoetin
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Side-effects:
GIT- constipation (usually), diarrhea, vomiting, epigastric pain, gastric ulceration and darkening of stools.
Liquid preparation can stain the teeth, and injectable iron can cause tissue discoloration
Other- dizziness
The antianemics: Iron preparations and Epoetin
Drug-Drug interaction
Tetracyclines and penicillamine- combine with iron preparations and render the iron unabsorbable.
Antacids and cimetidine- decrease iron absorption and effects
Foods can impair iron absorption but they should be taken with iron to reduce GI discomfort.
Milk containing foods, coffee, tea and eggs are NOT given with iron because they delay iron absorption.
The antianemics: Iron preparations and Epoetin
Implementation
Encourage the patient to eat iron-rich foods like liver, lean meat, egg yolk, dried beans, green leafy vegetables.
Administer iron preparations orally with foods to decrease GI discomfort.
If increased absorption is necessary, administer IN BETWEEN meals with full glass of water or juice.
It is best to offer citrus juices because the vitamin C content can increase iron absorption.
Instruct the patient to swallow the whole tablet and remain upright for 30 minutes to prevent esophageal corrosion from reflux.
DO NOT administer iron together with or within 1 hour of ingesting tetracyclines, antacids, milk and milk-containing products.
Advise clients to increase fluid intake and consume fiber rich foods if constipation becomes a problem.
The antianemics: Iron preparations and Epoetin
Implementation
Warn the patient of possible iron poisoning if tablets are left within child’s reach. Emphasize that the therapeutic effect of iron therapy may not be apparent until several weeks.
If injecting a parenteral iron preparation, inject DEEP IM utilizing the Z-track method to avoid leakage into the subcutaneous tissues and skin.
Offer straw if giving liquid iron preparation to avoid staining the teeth.
To prevent undue alarm, instruct the patient that the stools may turn black or dark green. This is a harmless occurrence.
The antianemics: Iron preparations and Epoetin
Evaluation
The nurse evaluates the effectiveness of the drug therapy by determining that the client is not fatigued, with absence of pallor, and with hemoglobin results within desired range.
Erythropoietin
The mechanism of action of epoetin alfa
(Epogen)
This drug acts like the natural glycoprotein erythropoietin to stimulate the production of RBC in the bone marrow.
Erythropoietin
Clinical indications
It is given SUBCUTANEOUSLY or INTRAVENOUSLY for the treatment of anemia associated with renal failure or for patients on dialysis.
It is also used in patients for blood transfusion to decrease the need for blood in surgical patients.
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Erythropoietin
Pharmacodynamics: the adverse effects of epoetin alfa
CNS- headache, fatigue, asthenia, dizziness and seizures- these are due to the cellular response to the glycoprotein.
GIT- nausea, vomiting and diarrhea
CVS- hypertension, edema and chest pain due to increase RBC number
Erythropoietin
Implementation
Administer the drug SC or IV usually 3 times per week.
Monitor the IV access line if given IV. Do not mix with other solutions
Determine periodically the level of hematocrit and iron stores during therapy. If patient does not respond to the drug, reevaluate the cause of anemia.
Maintain seizure precaution on stand by as seizure can occur.
Provide comfort measures like small frequent feedings and pain medications for headache.
Provide thorough health teaching: need for lifetime injection
Erythropoietin
Evaluation
Monitor patient response to the drug= increased hemoglobin
Nursing Pharmacology
Dermatological Agents
Dermatological Agents
Agents which are applied and exert their effects where they are administered
Dermatological Agents
The target tissue for most agents is the SKIN
Topical therapy
Use of active drugs in an inactive vehicle like oil
Employs the use of topical preparations
Topical preparations
SOAKS
LOTIONS
SOLUTIONS
PASTE
CREAM
OINTMENT
POWDER
Commonly used topical agents
Caustics
Silver nitrate, Zinc chloride and Ferric subsulfate
Used for granulation tissues, epitheliomas and granulomas (benign skin tumors)
Applied directly over the lesions
Keratolytics
Lactic acid, Glycolic acids, Urea, Salicylic acids
Causes desquamation of skin and denaturation of skin proteins
Destroys the skin keratin
Applied over the skin lesions like acne, calluses, warts and tinea versicolor
Cytostatic agents
Anthralin, Tars, Liquid carbonic detergents
Suppresses the DNA synthesis of skin cells
Used for psoriasis, eczema, seborrheic dermatitis
Applied over the skin lesions
Cytotoxic agents
Cantharadin, Podophylin, Fluouracil
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Kill the cell by either binding to DNA microtubules, destroys mitochondria or inhibiting DNA synthesis
Used for warts (condyloma), basal cell carcinoma
Demelanizing agents - whitening
Hydroquinone- bleaching agent that inhibits TYROSINASE activity in the melanocytesà decreased melanin
Monobenzone- bleaching agent that is MORE potent than hydroquinone causing irreversible and permanent whitening à used in extensive vitiligo
Melanizing agents- darkening
Psoralens- promotes melanin production in the kin, used for psoriasis and mild vitiligo to darken the skin
Methoxalen- photosensitizer that makes the skin sensitive to UV rays, used for psoriasis
Anti-infectives
Antibacterial drugs like bacitracin, terramycin
Antifungal agents like clotrimazole, ketoconazole, nystatin, tolnaftate
Antiviral agents like zovirax
Scabicides and pediculocides
Gamma Benzene Hexachloride, Crotamiton, Benzoyl benzoate, Permethrin
Applied to body or hair to kill the parasites
Retinoids
Include natural compounds and synthetic derivatives of vitamin A
Effects on the skinà reduction of keratinization that leads to acne formation ; reduction of SEBUM production and removal of Propionebacterium acne
Retinoids
Tretinoin (Retin-A)- reduces acne formation
Applied topically at night before bedtime
Side-effects: skin peeling, erythema, burning and stinging sensation
Retinoids
Isotretinoin (ACCUTANE)
Normalizes the keratinization process of cell
Taken ORALLY
Adverse effect: TERATOGENIC
Pharmacology
Migrane/ Ophthalmic and ENT DRUGS
Migraine Drugs
The underlying cause of migraine is believed to be ARTERIAL DILATATION
May be due to release of bradykinin, serotonin and other chemicals
Migraine Drugs
The ERGOT derivatives are the most frequently used drug to treat migraine previuosly
Recently the TRIPTANs have been introduced
ERGOT derivatives
These agents cause CONSTRICTION of the blood vessels in the cranium and decrease the pulsation of the arteries
ERGOT derivatives
Dihydroergotamine
Ergotamine
Methysergide
ERGOT derivatives
Adverse effects
Numbness
Muscle pain
Chest pain
Arrhythmias
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ERGOTISM- nausea, vomiting, hypoperfusion, chest pain, confusion
ERGOT derivatives
NURSING RESPONSIBILITIES
Avoid prolonged use and over-use
Assess for presence of decubitus ulcer and gangrene
Give the medication BEFORE the pain occurs
Provide supportive measures
Teach about ergotism
The TRIPTANs
These agents BIND to serotonin receptors in the cranial blood vessels causing VASOCONSTRICTION
The TRIPTANs
Sumatriptan
Zolmitriptan
Naratriptan
Rizatriptan
The TRIPTANs
Can be given orally, nasally, and SC
The TRIPTANs
ADVERSE Effects
Numbness, tingling sensation,coldness
Dizziness
GI discomfort
Chest pain
The TRIPTANs
NURSING RESPONSIBILITIES
Administer the drugs before the pain worsens
Monitor blood pressure
Measures for safety
Give with food to decrease GI effects
Glaucoma
Increased intra-ocular pressure
Glaucoma
Two types
1. Open angle
2. Closed angle
Glaucoma
Glaucoma
MEDICAL MANAGEMENT
1. Laser surgery
2. Drug therapy to lower Increased IOP
MiOtics to cause cOnstriction
Adrenergics, beta-blockers and CAI to cause reduced production
Miotics
These are also called parasympathomimetic agents
Their action mimics the parasympathetic nervous system
The Cholinergic Agonists
DIRECTLY acts by occupying the receptor in the eyes
Pilocarpine
Direct acting cholinergic agonists
Pharmacodynamics
Similar to acetylcholine and directly act on the acetylcholine receptors
Pilocarpine
Parasympathetic stimulation will cause:
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DUMBELS
urination
miosis (pupil constriction)
Pilocarpine
Clinical use
1. Relief of increased intraocular pressure of glaucoma by inducing miosis
Pilocarpine
Direct acting cholinergic agonists: Adverse effects (DUMBELS)
CVS- bradycardia, heart block, hypotension
GIT- nausea, vomiting, diarrhea, increased salivation, lacrimation
GUT- sense of urgency, sphincter relaxation
Others- increased sweating, headache, miosis, photophobia, blurred vision
Pilocarpine
Nursing considerations
1. Assure proper administration of ophthalmic preparations
2. Provide safety precautions- because of poor visual acuity and blurred vision
3. Promote cool environment, maintain access to the bathroom (urination)
Other Drugs for Glacoma
CAI- acerazolamide
Adrenergic agent- epineprhine
The ANTI-cholinergics
Anticholinergics:
Prototype: Atropine
dicyclomine
glycopyrrolate
propantheline
scopolamine
The ANTI-cholinergics
Anticholinergics: pharmacodynamics
These agents work by BLOCKING or COMPETING with acetylcholine for the acetylcholine receptors
BEST taken BEFORE MEALS
Atropine
Depresses salivation
Decreases bronchial secretions
Mydriasis
Cyclopedia
Inhibits vagal response in the heart
Reverses cholinergic toxicity
Atropine
Scopolamine
Decreases nausea and vomiting associated with motion sickness
Anticholinergic
Contraindications of anticholinergic
1. Known allergy
2. Glaucoma
3. Bladder obstruction (like PBH)
Anticholinergic
Adverse effects: anticholinergic effects
CNS- blurred vision, pupil DILATION, photophobia, cycloplegia and increased Intraocular pressure
GI- dry mouth, constipation, bloatedness
CVS- tachycardia, palpitations
GU- urinary retention
Others- decreased sweating, flushing
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Anticholinergic
Nursing considerations
Provide comfort measures
Frequent mouth care
Provide increased fluids
Protect eyes fro lights
Advise to avoid hazardous activities
Provide high-fiber diet and laxative
Avoid extremes of temperature
Instruct to void before administering the drug
Anticholinergic
Nursing considerations
2. Monitor for toxicity:
3. Ensure adequate hydration to prevent hyperpyrexia
The ANTIHISTAMINES
Also called H1 blockers or H1 antagonists, these are agents designed to relieve respiratory symptoms and to treat allergic conditions.
The ANTIHISTAMINES
The anti-histamines are group according to the “generation”.
The FIRST GENERATION agents have greater anticholinergic effects and can cause more sedation and drowsiness! These agents cause drowsiness.
The SECOND GENERATION agents have fewer anticholinergic effects that is why they cause less sedation.
The ANTIHISTAMINES
The FIRST GENERATION ANTIHISTAMINES
1. Azatadine 11. Dimenhydrinate
2. Azelastine 12. Diphenhydramine
3. Brompheniramine 13. Hydroxyzine
4. Buclizine 14. Meclizine
5. Cetirizine 15. Methdilazine
6. Chlorpheniramine 16. Promethazine
7. Clemastine 17. Tripelenamine
8. Cyclizine 18. Carbinoxamine
9. Cyproheptadine 19. Trimeprazine
10. Dexchlorpheniramine20 Triprolidine
The ANTIHISTAMINES
The SECOND GENERATION ANTIHISTAMINES
Fexofenadine
Loratidine
Azelastine
Cetirizine
Anti-Histamine
These agents SELECTIVELY block the effects of histamine at the HISTAMINE-1 receptor sites in the target tissue by competing with histamine for receptor, decreasing the cellular responses
They also have anticholinergic and antipruritic properties.
Anti-Histamine
Clinical Indications for Use in respiratory system
1. rhinitis
2. allergic sinusitis
3. uncomplicated urticaria and angioedema.
4. Motion sickness
Anti-Histamine
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1. CNS- drowsiness and sedation, most pronounced if first generation agents are used
2. Fatigue, dizziness and disturbed coordination.
3. Anticholinergic effects= drying of the respiratory mucus membrane, GI upset and nausea, arrhythmias, dysuria, urinary retention
4. Skin dryness
Anti-Histamine
Implementation
The nurse should administer the drug on an EMPTY stomach, or 1 hour before or 2 hours after meals to increase the absorption.
Give with food if GI upset occurs
Anti-Histamine
Implementation
Offer sugarless lozenges or hard candy to counteract dryness of the mouth. Give frequent oral care
Provide safety measures if drowsiness may occur. Side rails up, assist in ambulation, and advise not to drive or operate dangerous machineries or delicate tasks.
Anti-Histamine
Nursing implementation
Increase humidity in the room by utilizing nebulizers and provide adequate hydration
Allow the patient to void first before administering the drug.
Anti-Histamine
Evaluation
Monitor patient’s response to the drug, the adverse effects and the effectiveness of comfort measures employed
Decreased allergic symptoms
Decreased occurrence of rhinitis
The Topical Nasal Decongestants
These include:
Ephedrine
Oxymetazoline
Phenylephrine
Tetrahydrozoline
Xylometazoline
The Topical Nasal Decongestants
Pharmacodynamics: action
These agents imitate the effects of the sympathetic nervous system to cause vasoconstriction, leading to decreased edema and decreased inflammation of the nasal membranes.
The Topical Nasal Decongestants
Pharmacokinetics: administration and preparations
These agents are available as nasal sprays or drops used to relieve the discomfort of nasal congestion
Topical Decongestants
Clinical use of the agents
symptoms of nasal congestion in colds, rhinitis, and sinusitis.
These can be used when dilation of the nares is desired to facilitate medical examination and to relieve the pain and congestion of otitis media.
Topical Decongestants
Contraindication and precautions
erosions of the nasal mucosa.
These following conditions need precautions- narrow angle glaucoma, hypertension, diabetes, thyroid diseases, and CAD because these conditions may be aggravated by the sympathetic activity.
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Topical Decongestants
Pharmacodynamics: the drug effects
Local effects- local stinging and burning, erosions and ulceration if used for prolonged time.
If used for more than 5 to 10 days, rebound congestion can occur, also called rhinitis medicamentosa. The reflex reaction to vasoconstriction is a rebound vasodilatation as the drug effect wears off.
Sympathomimetic effects= tachycardia, hypertension, urinary retention.
Topical Decongestants
Nursing Responsibilities
Teach the patient the proper administration of the drug to ensure therapeutic effect.
The patients must clear the nasal passages first before use; tilt the head back when applying and keep tilted for a few seconds after administration
Emphasize that the drugs should NOT be used for more than 5 to 10 days and to seek medical attention if symptoms persist.
Topical Decongestants
Provide safety measures if dizziness or sedation occur to prevent injury
Institute other measures to help relieve discomfort of congestion like humidity, increased fluid intake, cool environment and avoidance of smoking
Anesthetics
Pharmacology in Nursing
Anesthetics
Anesthetics are drugs that are used to cause complete or partial loss of sensation.
The numerous anesthetics can be broadly classified as :
General
Local anesthetics
Anesthetics
General anesthetics
are central nervous system depressants used to produce loss of pain sensation and consciousness.
Anesthetics
Local anesthetics
are drugs used to cause loss of pain sensation and feeling in a designated area of the body without the systemic effects associated with severe CNS depression
General Anesthetics
Produce the following effects:
analgesia (loss of pain sensation),
unconsciousness and
amnesia
General Anesthetics
Blockage of autonomic reflexes prevents response of involuntary reflexes to injury to the body that might compromise a patient’s cardiac, respiratory, gastrointestinal and immune status.
Blockage of muscle reflexes prevents jerking movements that might interfere with the success of the surgical procedure.
Stages of Anesthesia Depth
Usually trained individuals with the special equipments ready for life support administer the agents
The patient undergoes through a predictable stages known as STAGES of ANESTHESIA: 1 to 4
Stages of Anesthesia
STAGE 1
Referred to as the Analgesia Stage is loss of pain sensation
with the patient still conscious and able to communicate
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Stages of Anesthesia
STAGE 2- the Excitement Stage,
A period of excitement and often combative behaviors are present such as restlessness, with signs of sympathetic stimulation (tachycardia, increased respiration and blood pressure changes)
Stages of Anesthesia
STAGE 3
Surgical Anesthesia stage, involves relaxation of skeletal muscles, return of regular respiration, and progressive loss of eye reflexes and pupil dilatation.
This is the best stage for surgical procedure.
Stages of Anesthesia
STAGE 4
Medullary Paralysis stage is a very deep CNS depression with loss of respiratory and vasomotor center stimuli in which death can occur rapidly.
General Anesthesia
INHALATIONAL (gas and volatile liquid)
Halothane
Enflurane
Nitrous oxide
INTRAVENOUS
Barbiturates (Thiopenthal and Methohexital)
Ketamine
Profofol
General Anesthetics
Action of General Anesthetics
The mechanism is not clear. It is known that depression of the reticular activating system and the cerebral cortex occurs.
Therapeutic use of General Anesthetics
Sedation and anesthesia for surgical procedures
General Anesthetics
The anesthetics are administered by trained personnel
Maintain equipment on standby to provide airway and mechanical ventilation in cases of severe drug reaction
Monitor temperature regularly, monitor pulse, BP and respiration
Carefully monitor patient in the recovery room until he regains consciousness and able to communicate
Provide safety and comfort measures.
Pre-operative teaching must be provided and information about the anesthetics should be incorporated in the teaching plan.
Local Anesthesia
Local anesthetics are drugs that cause a loss of sensation in limited areas of the body to abolish pain.
They are powerful nerve blockers injected locally.
Systemic absorption of the anesthetics can produce numerous side effects.
Local Anesthesia
Administering Local Anesthetics
There are five types of local anesthetic administration- topical, infiltration, field block, nerve block, and IV regional anesthesia.
Topical Administration- anesthetic agents are incorporated in vehicles such as creams, ointments, gels, lotions, drops and sprays.
Infiltration- this involves injecting the anesthetic directly into the tissues to be treated.
Local Anesthesia
Field block – involves injecting the anesthetic agents al around the area that will be affected by the surgical operation.
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Nerve Block- involves injecting the anesthetic agents at some point along the nerve that runs to and from the region of operation. One example is epidural anesthesia.
Intravenous regional Anesthesia involves carefully draining all of the blood from an arm or leg, securing a tourniquet to prevent the aesthetic from entering the
Local Anesthesia
Examples of Local anesthetics: The “CAINES”
Lidocaine
Dibucaine
Procaine
Tetracaine
Local Anesthesia
Local anesthetics work by causing a temporary interruption in the production and conduction of nerve impulses.
They affect the permeability of sodium (preventing it from entering the cell) and chloride (by entering the cell).
The nerve cells become more negative, with resultant decrease in depolarizationà no transmission of pain
Local Anesthesia
These agents are used for infiltration anesthesia, peripheral nerve block, spinal anesthesia and relief of local pain.
Local Anesthesia
The side effects of local anesthetics
Local effects- local irritation and skin breakdown
CNS effects if systemic absorption occurs- headache, restlessness, anxiety, dizziness, tremors and blurred vision.
GI system- nausea, vomiting
Cardio- arrhythmias, peripheral vasodilation, myocardial depression, and rarely, cardiac arrest
Local Anesthesia
Nursing Responsibilities
Maintain emergency equipment on standby to provide life-support in cases of severe reactions
Ensure that drugs are available for managing hypotension, cardiac arrest and CNS alterations.
Provide adequate hydration to patients receiving spinal anesthesia. Position the client supine for up to 12 hours after spinal anesthesia to minimize spinal headache
Local Anesthesia
Nursing Responsibilities
Provide safety and comfort measures such as side-rails up, frequent skin care and supportive care
Give health teaching to explain things the patient needs to know to allay fears.
Muscle Relaxants
Pharmacology in Nursing
Overview
Skeletal muscle relaxants are drugs that decrease muscle tone and movements by reducing skeletal muscle activities
Types of Relaxants
Central acting: Baclofen, Chlorphenesin, Chlorzoxazone
Peripheral Acting: “Curium” and “curare”
Direct acting: Dantrolene
Central Acting Relaxants
These agents DEPRESS the CNS or BLOCK the transmission of nerve impulses from the spinal cord to the skeletal muscles
The result is muscle relaxation
Peripheral Acting Relaxants
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These agents interfere with nerve transmission between the motor end plate and the skeletal muscle receptors
These agents block the DEPOLARIZATON and REPOLARIZATION activity of the skeletal muscles leading to PARALYSIS
BACLOFEN (Lioresal)
Pharmacodynamics: inhibits the synaptic reflexes at the SPINAL cord
The action does not reduce consciousness
This is prescribed for the treatment of spasticity and muscle sprain; also as adjunct to physical therapy
BACLOFEN (Lioresal)
Kinetics: absorbed orally, excreted in the feces and kidney.
Thus drug is very lipophilic that can pass the brain barrierà drowsiness
BACLOFEN (Lioresal)
Side-effects:
CNS: Drowsiness, dizziness and confusion
CVS: Hypotension, bradycardia
GU: Urinary frequency and impotence
BACLOFEN (Lioresal)
Nursing Responsibilities:
Avoid the use together with alcohol
Perform a baseline mental status examination
Supervise any ambulation and transfers to ensure safety
Monitor blood pressure
Check deep tendon reflexes for any symptom of toxicity
BACLOFEN (Lioresal)
Evaluate for effectiveness of the drug
The client displays evidence of increased range of motion exercise
Decreased spasticity
Dantrolene
Pharmacodynamics: this agent acts DIRECTLY on skeletal muscle to interfere with CALCIUM release from the sarcoplasmic reticulum
This is useful in conditions like: MALIGNANT hyperthermia and spastic conditions like multiple sclerosis, spinal cord injury and CVA
Dantrolene
Kinetics: absorbed orally, can be given IV, excreted in kidney
Dantrolene
Side-effects:
CNS: muscle weakness, drowsiness and dizziness
CVS: tachycardia an phlebitis
GIT: HEPATITIS
GU; Urinary frequency, hematuria and retention
Dantrolene
Nursing Responsibility
Note that this drug is not used if patient has liver dysfunction as hepatitis can occur
Peripheral Acting Relaxants
Usually group into: NON-DEPOLARIZING and DEPOLARIZING agents
NON-DEPOLARIZING are COMPETITIVE agents that BLOCK acetylcholine receptors
DEPOLARIZING agent excites the muscle initially then prevents the muscle from contracting
Peripheral Acting Relaxants
Non DEPOLARIZING Agents:
Atracurium besylate
Pancuronium
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Rocuromium
Vecuronium
Tubocurarine
DEPOLARIZING
Succinylcholine
Peripheral Acting Relaxants
General indications:
Adjunct to general anesthesia
Muscle relaxation during surgery, mechanical ventilation and orthopedic manipulation
Peripheral Acting Relaxants
Side effects
Respiratory depression
Muscle weakness
Cardiac arrhythmias
Hypotension
Peripheral Acting Relaxants
Nursing Responsibilities
Note that paralysis occurs from head to toe and recovery starts from toe to head
Monitor the BP and respiratory status frequently
Note that consciousness in NOT affected
Peripheral Acting Relaxants
Evaluate for drug usefulness
The client will maintain skeletal relaxation without respiratory depression
Peripheral Acting Relaxants
Succinylcholine
A depolarizing agent that prolongs the depolarization of the muscle end plate
Used as muscle relaxant during surgery, intubation and short procedures
Administered IV, relaxation occurs in 1 minute and lasts for 6 minutes
COMPUTATIONS
Oral Medications: Solids
Quantity of Drug =
Desired dose/Stock dose
(D/S = Q)
Oral/Parenteral: Liquids
Quantity of Drug =
Desired dose
--------------------- X Dilution
Stock dose x
(D/S x dilution = Q)
IV Fluid Flow Rate
gtts/min
Vol. in cc x gtt factor
----------------------------
no. of hours x 60 mins.
IV Fluid Flow Rate
cc/hr
Vol. in cc
-------------------------
no. of hours
IV Fluid Flow Rate
Duration in hours
Vol. in cc
-------------------------
cc/hr
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Conversion of Temp
oC to oF
(oC x 1.8) + 32
oF to oC
(oF – 32) (.55)
THANK YOU.
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