Central Nervous System DRugs

7/29/2019 Central Nervous System DRugs

1/78

Drugs Affecting the Central

Nervous System

Chapter 5


2/78

Central Nervous System CNS

CNS

Brain and Spinal Cord

Acts as control for regulating physical and mental

processes

Neurons are the brains functional units


3/78

Neurons

The brain is a collection of about 10 billion

interconnected neurons. Each neuron is a

cell that uses biochemical reactions to

receive, process and transmit information.


4/78

Neurotransmitters

Chemical substances that carry messages

from one neuron to another or from a neuron

to other body tissues, such as cardiac or

skeletal muscles.


5/78

Synapses

The synapse is a small gap separating

neurons.


6/78


7/78

Receptors

Proteins embedded in the cell membranes of

neurons.

A neurotransmitter must bind to receptors to

exert an effect on the next neuron in thechain.


8/78

Major Components of CNS

Cerebral Cortex

Thalamus

Hypothalamus


9/78

Cerebral Cortex

Involved in all conscious process learning,

memory, reasoning, verbalization, voluntary

body movements


10/78

Thalamus

Sensation of heat, cold, pain, and muscle

position

Relays motor impulses from the cortex to the

spinal cord


11/78

Hypothalamus

Neuro-endocrine functions

ADH fluid balance

Body temperature

Regulating arterial blood pressure

Appetite and hunger

Physical changes associated with emotions


12/78

Brain

Needs 3 things to properly function

Oxygen requires more oxygen than any other

organ

Glucose energy source Thiamine needed for production and use of

glucose


13/78

Drugs That Effect CNS

Depressants

Stimulants


14/78

CNS Depressants

Mild CNS depressant: decreased interest in

surroundings, inability to focus

Moderate CNS depressant: drowsiness or

sleep, decreased perception of heat or cold

Severe CNS depressant: unconsciousness or

coma, loss of reflexes, respiratory failure and

death


15/78

CNS Stimulation

Mild stimulation = wakefulness, mental

alertness, and decreased fatigue

Moderate stimulation = hyperactivity,

excessive talking, nervousness, andinsomnia

Excessive stimulation: confusion, seizures,

cardiac dysrhythmias


16/78

Pain

Pain occurs when tissue damage activates

free nerve endings of peripheral nerves

Nociceptors are located in skin, soft tissue,

muscle fascia, joint surfaces, arterial wallsand periosteum


17/78

Nociceptors


18/78

Opioid Analgesics

Opioid analgesics relieve moderate to severe

pain in both the central and peripheral

nerves.


19/78

How do they work?

Decrease pain sensation in brain

Produces sedation

Decreases emotional upset associated with

pain

Inhibits production of pain inflammation by

prostaglandins


20/78

Opioids

How given:

by mouth need high dosages due to first

pass through liver

Intramuscular

Intravenous


21/78

Opioids Effect on Body

CNS depressant - drowsiness to sleep to

unconsciousness to coma

Respiratory can cause severe respiratory

depression

Gastrointestinal: slows gastric motility

constipation


22/78

Caution

Patient with

Respiratory depression

Chronic lung disease

Liver / kidney disease

Allergy to drug


23/78

Schedule II Drugs

Classification

Opioid analgesics

Morphine

Codeine often used in combination withacetaminophenTylenol with codeine

HydrocodoneVicodin - used in combination withacetaminophen / aspirin / ibuprofen

HydromorphineDilaudid - More potent thanmorphine

MeperidineDemerol OxycodonePercocet (with acetaminophen) or

Percodan (with aspirin)


24/78

Morphine Sulfate

Therapeutic classification: opioid analgesic

Pharmacology classification: Opioid agonist

Indications: severe pain (postoperative,

fractures, burns) pulmonary edema, and pain

associated with myocardial infarct (MI)


25/78

Morphine

Action: Binds to opiate receptors in the CNS.

Alters the perception of and response to

painful stimuli while producing generalized

CNS depression Therapeutic Effects:decrease in severity of pain

Adverse Reactions: severe respiratory

depression, constipation


26/78

Morphine Side Effects

IV maximal analgesia and respiratory

depression would occur within 10 to 20

minutes

IM: within 30 minutes

Sub Q: 60 to 90 minutes

PO: peak activity occurs in about 60 minutes

* higher dosage needed to metabolism ofdrug in the liver


27/78

Morphine Dosing

Tablets come in 15 mg, 15 mg or 30 mg

Solution for IM, IV or sub Q: 10 mg/ml most

common


28/78

Nursing Responsibilities

Pain assessment use appropriate tools

Base-line vitals

Re-asses vitals after pain med administered

Assess bowel function

Overdose: Narcan used to reverse

respiratory depression


29/78

Pain Scales

Numeric 1-10

FACES


30/78

Assessment

Pain is a subjective experience (whatever a patient

says it is) and there are a wide variety of responses

to pain.

Culture may effect a persons response Anxiety or depression can increase ones perception

of pain

Fatigue, anger and fear tend to increase pain

Change in vital sign are not always accurateindicators of a patients pain


31/78

Evaluation of Effectiveness

Decrease in severity of pain without a

significant alteration in level of consciousness

or respiratory status.

JCAHO standards dictate that a nurse willevaluate the patients response to the pain

medication within 30 minutes to one hour

after administration of the pain medication.


32/78

Codeine

Therapeutic Classification: allergy, cold and

cough remedies, antitussives, opioid

analgesics

Pharm classification: opioid agonist

Schedule II drug


33/78

Codeine

Action: Binds to opiate receptors in the CNS.

Alters the perception of and response to

painful stimuli while producing generalized

CNS depression decreases cough reflexdecreases GI motility


34/78

Codeine

Side Effects: confusion, sedation,hypotension, constipation

Nursing responsibilities - same as morphine

Evaluation of effectiveness: Decrease in severity of pain without significant

alteration in level of consciousness

Suppression of cough

Control of diarrhea


35/78

Codeine

Therapeutic Effects:

Decrease severity of pain

Suppression of a cough reflex

Relief of diarrhea


36/78

Codeine Dosing

Usually supplied in combination with other

analgesics

Tylenol with codeine

Tylenol # 2 = 15 mg codeine Tylenol # 3 = 30 mg codeine

Tylenol # 4 = 60 mg codeine

Most often given po with food


37/78

Meperidine

Demerol is a synthetic drug with the same

uses and adverse effects as morphine

Less nausea and vomiting

Use with caution due to neurotoxic

metabolism with chronic use CNS agitation

and confusion, hallucinations, seizures and

tremors


38/78

Meperidine Dosing

IV or IM

Provided as 10 mg/mL, 50 mg /mL, 75

mg/mL or 100 mg/mL

Dosage for adults: 50 to 150 mg every 3-4

hours

Dosage for pediatrics: 1 to 1.8 mg / kg q 3-4

hours (not to exceed 100 mg dose)


39/78

Opioid Antagonists

Block or reverse analgesia, CNS, respiratory

depression

Competes with opioids for opioid receptor

sites in the brain and prevents opioid bindingwith receptors or displaces opioids that have

already occupied the receptor sites.


40/78

Naloxone or Narcan

Naloxone is the oldest and has long been the

drug of choice to treat respiratory depression

caused by an opioid drug.

IV, IM or Sub Q acts in minutes and last for 1to 2 hours


41/78

Use in Special Populations

Opiate tolerant clients

Pediatric patients

Geriatric population

Renal and hepatic impairment

Critical Care

Cancer


42/78

Chapter 7

Analgesic Antipyretic Anti-

inflammatory


43/78

Prostaglandins

Chemical mediators found in most body

tissue they help regulate many cell

functions and participate in the inflammatory

response


44/78

PainFever - Inflammation

Pain can occur with injury or tissue

inflammation

Fever is elevation of body temperature above

the normal range.

Inflammation is the normal body response to

tissue damage it is the attempt by the body

to remove the damaging agent and repair thedamaged tissue.


45/78

Mechanism of Action

Aspirin and other NSAIDs inhibit

prostaglandin synthesis in the central

nervous system and the periphery.

Acetaminophen action on prostaglandin islimited to the central nervous system less

effective in reducing inflammation.

Both inhibit cox enzymes which are requiredfor prostaglandin formation


46/78

Indications for Use

Aspirin, NSAIDs and acetaminophen are

used to prevent and treat mild to moderate

pain and or inflammation associated with

musculoskeletal disorders, headache,menstrual cramps, minor trauma, or minor

surgery


47/78

Aspirin

Usage has declined since new NSAIDs

developed.

Cause GI upset GI bleeding

Low dosage ASA used as preventive

measure against stroke or myocardial

infarction

Contraindicated in children due to RyesSyndrome


48/78

Acetaminophen

Commonly used as an aspirin substitute for

fever and pain but lacks the anti-inflammatory

and anti-platelet effects.


49/78

Tylenol Most Common Brand

Action: inhibits the synthesis of

prostaglandins that may serve as mediators

of pain and fever, primarily in the CNS. Has

no significant anti-inflammatory properties orGI toxicity.

Metabolism: 85-98% by the liver may be

toxic in overdose situation excreted bykidneys.


50/78

Drug-drug interaction

Chronic high dose acetaminophen (greater than 2

gram per day) may increase the risk of bleeding with

Warfarin (Coumadin)

PT should be monitored and INR not to exceed 4

Hepatotoxic with other hepatotoxic substances

including alcohol.

Combines use with NSAIDs increased risk of

adverse renal effects. May decrease effects of loop diuretics - Lasix


51/78

Overdose

Advise parents or caregivers to check

concentrations or liquid preparations. Errors

can result in serious liver damage.

Treatment for overdose is Mucomyst.


52/78

Dosages

Drops: 80 mg per 0.8 mL

Suppository: 80 mg or 120 mg

Chewable tablets: 80 mg or 160 mg

Liquid or elixer:

160 mg per 5 mL

500 mg per 5 mL

80 mg per 2.5 mL


53/78

Dosing

Adults: 325 to 650 mg every 4-5 hours or 1

gram 3-4 times daily or 1300 mg every 8

hours.

Pediatrics: 10 to 15 mg / kg / dose q 4-6hours


54/78

NSAIDs

Ibuprofen Advil

Therapeutic classification: antipyretic, anti-

rheumatics, nonopioid analgesic, non-

steroidal anti-inflammatory Pharm classification: nonopioid analgesics

Action: inhibits prostaglandin synthesis

decreases pain, fever, and inflammation Caution against use with alcohol


55/78

NSAIDs

Naproxen Naprosyn

Naproxen sodium or Aleve

Do not mix with other OTC anti-inflammatory

drugs ASA, acetaminophen.

Caution use with alcohol 3 or more glasses

a day

Administer with food to decrease GI upset

id l A i i fl D


56/78

Nonsteroidal Anti-inflammatory Drugs

Davis Drug Guide

Dicofena

Etodolac

Ibuprofen Ketoproften

Ketoriac

Naproxen Rofecoxib

Valdecoxib

d


57/78

Contraindications

Peptic Ulcer

GI or other bleeding disorders

Impaired renal function

Allergy to the drug

C T U


58/78

Common Long Term Uses

Relief of pain in osteoarthritis wear and tear

on joints causing the cartilage to wear away

especially knees and hips

Start with acetaminophen NSAIDS

Cox 2 inhibitors for decrease GI upset

Chondroitin and Glucosamine - OTC

Injection of cortisone into the joint

Synvise (chicken juice) to lubricate the joint

O h i i


59/78

Osteoarthritis

Rh id A h i i


60/78

Rheumatoid Arthritis

Systemic inflammatory disease often

effecting multiple joints

Aspirin 2 to 6 grams daily

NSAIDs to reduce GI upset

Corticosteroids and immunosuppressant's

Goal of drug therapy is to reduce the

symptoms

Rh id A h i i


61/78

Rheumatoid Arthritis

A f Cli


62/78

Assessment of Client

Assess for location severity, duration and

factors that cause or relieve the pain.

Assess for fever

Assess for sign of local inflammation:redness, swelling, heat, edema and

tenderness

System signs of inflammation: elevated WBC,erythrocyte sedimentation rate (ESR) and C-

reactive protein (CRP)

L b V l


63/78

Laboratory Values

WBC 7,000 to 25,000 with infection and up

to 50,000 in leukemia

E h S di i R


64/78

Erythrocyte Sedimentation Rate

Increases with inflammation

Nonspecific marker for inflammation

Normal rate 0-10

C R i P i


65/78

C-Reactive Protein

CRP, also known as C-Reactive Protein, is a

test which measures the concentration in

blood serum of a special type of protein

produced in the liver that is present duringepisodes of acute inflammation or infection.

CRP should be zero

A C i d


66/78

Assessment Continued

In musculoskeletal disorders look for reduced

ROM of extremities

Ask about allergic reactions to drugs

Assess for kidney or peptic ulcer disease orgastrointestinal bleeding


67/78

Drugs Affecting CNS

Chapter 8,9,10,11,12

A ti i t Dr d H p ti Dr


68/78

Anti-anxiety Drugs and Hypnotic Drugs

Anti-anxiety and sedative-hypnotic drugsCNS depressants

Anti-anxiety produces relaxation

Hypnotic produces sedation and sleep Work on the GABA neurotransmitters in the

brain and spinal cord

Used in: Anxiety disorder

Sleep and insomnia

A ti h ti D


69/78

Antipsychotic Drugs

Antipsychotic drugs most bind with

dopamine receptors to block action of

dopamine

Psychosis Schizophrenia


70/78

Antidepressants and Mood

Stabilizers

Chapter 9

D pr i


71/78

Depression

Thought to result from a deficiency of

norepinephrine or serotonin

Antidepressants increase the amounts of one

of both of these neurotransmitters in the CNSsynapse by inhibiting their reuptake in the

pre-synaptic neuron.

Depression


72/78

Depression

Most common mental illness characterized by

depressed mood, feeling of sadness or

emotional upset.

Mild depression occurs in everyone as anormal response to left stressors and losses.

No need for treatment

Major Depression


73/78

Major Depression

As defined by the American Psychiatric AssociationsDiagnostic and Statistical Manual Disorders

Loss of energy, fatigue

Indecisiveness

Difficulty, thinking and concentrating

Loss interest in appearance, work and leisure and sexual

activities

Inappropriate feelings of guild and worthlessness

Loss or appetite or excess eating

Sleep disorders (hypersomnia or insomnia)

Obsession with death, thoughts of suicide

Anti Seizure Drugs


74/78

Anti Seizure Drugs

A seizure involves a brief episode ofabnormal electrical activity in nerve cells of

the brain

Epilepsy is a chronic, recurrent pattern ofseizure activity

Anti-seizure drugs can usually control the

seizure activity but do not cure the underlyingdisorder.

Anti Seizure Drugs


75/78

Anti-Seizure Drugs

Drugs are thought to suppress seizures by;

Decreasing movement of ions into the nerve cell,

by altering the neurotransmitters (GABA)

Blocking these ions decreases responsiveness tostimuli

Anti Parkinson Drugs


76/78

Anti-Parkinson Drugs

Parkinsons disease is a chronic progressive,degenerative disorder of the central nervous

system characterized by abnormalities in

movement and posture (tremor, bradyknesia,joint and muscular rigidity, postural instability)

Parkinsons Disease


77/78

Parkinson s Disease

Thought to be an imbalance betweendopamine and acetylcholine in the CNS

Drug being developed are focusing on these

area

CNS Stimulants


78/78

CNS Stimulants

Two disorders treated with CNS stimulantsare narcolepsy and Attention Deficit

Hyperactivity Disorder

CNS stimulants act by facilitation initiationand transmission of nerve impulses that

excite other cells.

New drugs act selectively to inhibit reuptakeor norepinephrine in the nervous system.

Central Nervous System DRugs

Documents