Awareness of antibiotics

Awarenessof Antibiotics

BYDr Hussein FatehyConsultant pulmonologist

PhD-FCCP-MCTSAbbassia Chest Hospital

AntibioticsAntibioticsDefinitionDefinition

Antibiotics are substances that Antibiotics are substances that kill or inhibit the growth of kill or inhibit the growth of micro-organisms.micro-organisms.Bacteriostatic (Tetracycline, Bacteriostatic (Tetracycline, Chloramphenicol)Chloramphenicol)Bactericidal (Beta lactams, Bactericidal (Beta lactams, Aminoglycosides)Aminoglycosides)

..

HistoryThanks to work by Alexander Fleming (1881-1955), Howard Florey ( 1898-1968) and Ernst Chain (1906-1979), penicillin was first produced on a large scale for human use in 1943. At this time, the development of a pill that could reliably kill bacteria was a remarkable development and many lives were saved during World War II because this medication was available.

E. Chain H. FloreyA. Fleming BC Yang

Why take antibiotics?Why take antibiotics? "The desire to take "The desire to take

medicine is perhaps the medicine is perhaps the greatest feature which greatest feature which distinguishes man from distinguishes man from animals." animals."

"One of the first duties of "One of the first duties of the physician is to educate the physician is to educate the masses not to take the masses not to take medicine" medicine"

H. Cushing, Life of Sir William Osler (1925)

William Osler, MD (1849 - 1919)

Indications for antibacterial therapy:

1. Definitive therapy

•This is for proven bacterial infections

•Attempts should be made to confirm the bacterial infection by means of staining of secretions/fluids/exudates, culture & sensitivity, serological tests & other tests

•Based on the reports, a narrow spectrum, least toxic, easy to administer & cheap drug should be prescribed.

2. Empirical therapy• Empirical antibacterial therapy should be restricted to critical cases, when time is inadequate for identification & isolation of the bacteria & reasonably strong doubt of bacterial infection exists:

- septicemic shock/sepsis syndrome

- immunocompromised patients with severe systemic infection

- hectic temperature

- neutropenic patient (reduction in neutrophils)

In such situations, drugs that cover the most probable infective agent/s should be used.

Empiric antibiotic is antibiotic therapy that is begun before a specific pathogen is identified

3. Prophylactic therapy

• Certain clinical situations require the use of antibiotics for the prevention rather than the treatment of infections.

• In all these situations, only narrow spectrum & specific drugs are used

• The duration of prophylaxis is dictated by the duration of the risk of infection.

• eg.

1. Prevention for persons from non-malarious areas who visit areas endemic for malaria.

2. Treatment prior to certain surgical procedures to prevent infections

Bacteria vs Host

Bacteria Host

Pathogen Vs non pathogen

Virulence

Host defence

antibiotic

Disease

Selection of antimicrobial

agents

Factors should be considered before prescribing antibacterial

agent1.Site of infection

2.Type of infection

3.Severity of infection

4.Isolate & its sensitivity

5.Source of infection

6.Patient factors

7.Drug-related factors

1. Site of infectionInfection above the diaphragm:

•URTI eg pharyngitis, tonsilitis, sinusitis, otitis, epiglottitis etc.

- commonly caused by organism like Strep. pyogenes, S. pneumoniae, Fusobacteria, Peptostreptococci (rarely Mycoplasma, H. influenzae)

- Can be treated with drugs like penicillins

macrolides

cephalosporins

1. Site of infection…con’tLower respiratory tract infections:

Eg. Bronchitis, pneumonitis, pneumonia, lung abscess etc

-generally caused by the organisms Strep. pyogenes, S. pneumoniae, Fusobacteria, Peptostreptococci, Staph aureus (rarely Mycoplasma, H. influenzae, Moraxella, Klebsiella) etc.

- can be treated penicillins, cephalosporins, macrolides & tetracylines

1. Site of infection …. con’t

Infection below the diaphragm:

•Eg UTI, intra-abdominal sepsis, pelvic infections etc --- these are caused by the organisms like E. coli, Klebsiella, Proteus, Pseudomonas, Bacteroides etc.

• Quinolones, aminoglycosides, 3rd generation cephalosporins & metronidazole alone or in combination are useful in these infections.

Rule of the thumb

Infections above the diaphragm Cocci & Gram +ve organisms

Infections below the diaphragm Bacilli & Gram -ve organisms

1. Site of infection …. con’t

• There are certain sites where the infection tends to be difficult for treatment :

- meningitis (impenetrable BBB),

- chronic prostatitis (non-fenestrated capillaris),

- intra-ocular infections (non-fenestrated capillaries),

- abscesses (thick wall, acidic pH, hydrolizing enzymes etc.),

- cardiac & intravascular vegetations (poor reach & penetration),

- osteomyelitis (avascular sequestrum) etcIn such cases:- Higher & more frequent dose Longer duration of therapy Combinations Lipophilic drugsmay have to be used

2. Type of infection

Infections can be localised/extensive; mild/severe; superficial/deep-seated; acute/sub acute/chronic & extracellular/intracellular.

For extensive, severe, deep-seated, chronic & intracellular infections –

• Higher & more frequent dose

• Longer duration of therapy

• Combinations

• Lipophilic drugs

may have to be used

3. Severity of infections• Bacteremia / sepsis syndrome / septic shock;

• abscess in lung / brain/ liver/ pelvis/ intra-abdominal;

• meningitis/ endocarditis/ pneumonias / pyelonephritis / puerperal sepsis;

• Severe soft tissue infections / gangrene & hospital acquired infections

For severe infections only IV route - to ensure adequate blood levels. only bacterial drugs - to ensure faster clearance of the infection. dose should be higher & more frequent.

- If the site is unknown, attempt should be made to cover all possible organisms, including drug resistant Staphylococcus, Pseudomonas, & anaerobes.

- A combinations of Penicillins / 3rd generation cephalosporins, aminoglycosides & metronidazole may be used.

4. Isolate & sensitivity• Ideal management of any significant bacterial infection requires culture & sensitivity (C&S) study of the specimen.

• If the situation permits, antibacterials can be started only after the sensitivity report is available.

• Narrow spectrum, least toxic, easy to administer & cheapest of the effective drugs should be chosen.If the patient is responding to the drug that has

already been started, it should not be changed even if the in vitro report says otherwise

5. Source of infection

Community-acquired infections are less likely to be resistant

whereas

Hospital-acquired infections are likely to be resistant & more difficult to treat (eg. Pseudomonas, MRSA etc)

6. Patient factors

• Factors should be considered in choosing the antibacterial agent:

- Age of the patient

- immune status

- pregnancy & lactation

- associated conditions like renal failure, hepatic failure, epilepsy etc.

• In infants, chloramphenicol (can cause grey baby) & sulpha drugs (can cause kernicterus) are contraindicated

• In the elderly, achlorhydria may affect absorption of anticbacterial agents; drug elimination is slower, requiring dose adjustments & ototoxicity of aminoglycosides may be increased.

Patient factors…….con’t

Children

Elderly

- Tetracycline are contraindicated < 8 years because they discolour the teeth- < 18 years ALL fluoroquinolones are contraindicated because they cause arthropathy by damaging the growing cartilage.

• In patients with likelihood of compromised immune status, like extremes of age, HIV infection, diabetes mellitus, neutropenia, splenectomy, using corticosteroids or immunosuppresants, patients with cancers/blood dyscrasias, ONLY bactericidal drugs should be used.

Patient factors…….con’t

Patients with compromised immune status

Patient factors…….in pregnancyContraindicated in all trimesters Contraindicated in the last

trimesters

Safe in pregnancy Contraindicated in lactating mothers

• tetracylines

• quinolones

• streptomycin

• clarithromycin

• sulpha drug

• nitrofurantoin

• chloramphenico

l

•penicillins

•cephalosporins

•erythromycin

•isoniazid

•ethambutol

• sulpha drug

• tetracylines

•nitrofurantoin

• quinolones

•metronidazole

Drugs with limited data on safety like aminoglycoside, azithromycin, clindamycin, vancomycin, metronidazole, trimethoprim, rifampicin & pyrazinamide should be used with caution when benefits overweigh the risks

Patient factors…….in patients with renal failure

Absolutely contraindicated Relatively contraindicated

Relatively safe

It is better to avoid combinations of cephalosporins & aminoglycosides in these patients because both classes can cause nephrotoxicity

• tetracycline

•Penicillins

•Macrolides

•Vancomycin

•Metronidazole

•Isoniazid

•Ethambutol

•Rifampicin

•Aminoglycoside

•Cephalosporins

•Fluoroquinolones

•Sulpha drug

Patient factors…….in patients with hepatic

failureNo drugs are absolutely contraindicated.

Relatively contraindicated

Safe

•Chloramphenicol

•Erythromycin estolate

•Fluoroquinolones

•Pyrazinamide

•Rifampicin

•Isoniazid

•Metronidazole

•Penicillins

•Cephalosporins

•Ethambutol

•Aminoglycosides

7. Drug factors

1. Hypersensitivity: If the patient has prior history of hypersensitivity the antibacterial agent should be avoided. It is therefore important to elicit this history in all patients (common with penicillin)

2. Adverse reactions:Certain ADRs warrant discontinuation of therapy & the doctor should adequately educate the patients on these adverse effects.

7. Drug factors

3. Cost:

It should always be remembered that just because as particular drug is expensive, it need not be superior than the cheaper ones.

Eg. Cheaper drug like doxycycline or co-trimoxazole are as effective as the costlier clarithromycin or cephalosporins in the management of lower RTI.

7. Drug factors…….con’t

4. Interactions:Interactions with food & other concomitant drugs should be considered before instituting antibacterial therapy so as to maximize efficacy & minimize toxicity.

a) Interactions include enhanced nephrotoxicity or ototoxicity when aminoglycosides are given with loop diuretics, vancomycin or cisplatin.

b) Rifampicin, a strong inducer of hepatic drug-metabolizing enzymes, decreases the effects of digoxin, ketoconazole, oral contraceptives, propranolol, quinidine & warfarin.

c) Erythromycin inhibits the hepatic metabolism of a number of drugs, including phenytoin, terfenadine, theophylline & warfarin.

Methods of administration of antimicrobialsRoute of administration

The route of administration depends on the site, type & severity of the infection & the availability of a suitable drug

- Oral route is the most preferred, easy & cheap, but may not be reliable in all circumstances, esp. in patients with severe infections, non-compliant patients, in the presence of vomiting etc.

Certain drugs like the aminoglycosides & most 3rd generations cephalosporins are not available for oral administration.

- IM route should generally be restricted for the administration of procaine & benzathine penicillin.

The absorption is not very reliable & it is painful & dislike by the patients.

Route of administration…….con’t

- IV route is the best for the management of severe & deep-seated infections since it ensures adequate serum drug levels.

Procaine penicillin & benzathine penicillin should never be given IV.

•However, some drugs are not available for parental use (eg. Most macrolides, sulpha drugs, tetracyclines)

• Chloramphenicol, the fluoroquinolones & trimethoprim-sulphamethoxazole (TMP-SMZ) are also available orally.

• Antibacterials are also used topically

Switching from IV to Switching from IV to OralOral

Step-down therapyStep-down therapy: :

Conversion of an IV antibiotic to another oral Conversion of an IV antibiotic to another oral Transitional therapyTransitional therapy: :

Conversion from same IV antibiotic to oral Conversion from same IV antibiotic to oral but not of same dosage or strength but not of same dosage or strength

Sequential therapySequential therapy: :

Conversion from same IV antibiotic to oral of Conversion from same IV antibiotic to oral of same dosage and strength same dosage and strength

Dosage

- Dosage depends on patient’s age, weight, associated conditions like pregnancy, renal & hepatic failure & site, type & severity of infection.

- Generally the dose should be higher in cases of severe, deep-seated infections & lower in cases of renal-failure.

- Unnecessary overdosage only adds to the cost & adverse effects.

Frequency of administration

• The drug should be administered 4-5x the plasma half-life to maintain adequate therapeutic concentrations in the serum throughout the day.

• Frequency can be:-

- increased in cases of severe, deep seated & sequestrated infections

- reduced in cases of renal & hepatic failure.

Duration

• Duration of therapy depends on the site

1)Tonsilitis – 10 days

2) Bronchitis – 5-7 days

3) UTI – single shot to 21 days

4) Lung abscess- 2-4 weeks

5) Tuberculosis – 6-24 months

• Longer courses of therapy are usually required for infections due to fungi or mycobacteria

• Endocarditis & osteomyelitis require longer duration of treatment

Combinations1) For synergistic effect:

eg: combination of 2 bacteriostatic drugs such as

trimethoprim + sulfamethoxazole =

Co-Trimoxazole (bacterim®)

Therapeutic advantage of sulphonamide + trimethoprim

1) Synergistic effects

2) Bactericidal activity

3) Decrease resistance

4) Bigger spectrum of activity

5) Reduced toxicity

2) Treatment of infections with multiple organisms:

Mixed infections in lung abcess, peritonitis, soiled wounds etc naturally require multiple antibiotics for complete clearance of the infection – penicillins (for Gram +ve & certain anaerobes) & aminoglycosides (for Gram –ve); metronidazole for bacteroides.

penicillins + aminoglycosides + metronidazole

Combinations…….con’t

3) To prevent resistance: Use of combination is a well known method of preventing drug resistance. The classic example is the antiTB therapy, Eg isoniazid + ethambutol + rifampicin

4) To overcome resistance: Combination of specific drugs can be useful in overcoming that resistant infections, egPenicillins + -lactamase inhibitors (Co-amoxiclav/augmentin)

Combinations…….con’t

The following combinations are irrational, not useful or even harmful:

1) Bactericidal with bacteriostatic

eg. Penicillins (bactericidal) with tetracyclines ( bacteriostatic)

Bactericidal a/b (kill bacteria) – tend to be used in combination with one another

Bateriostatic a/b (prevent bacteria’s reproduction) – tend to be used on its own

2) Combinations of drugs with similar toxicity

eg. Chloramphenicol & sulpha drug

3) Combining drugs for non-existing “mixed infections”

eg. Tablets of ciprofloxacin + metronidazole/tinidazole

Clinical failure of antimicrobial

therapy

Failure of an antibiotic regimen (1)

1) Drug factors

• incorrect choice,

• poor tissue penetration

• inadequate dose

• pH – low pH reduces effectiveness of aminoglycosides, erythromycin, clindamycin

Inadequate clinical or microbiological response to antimicrobial therapy can result from multiple causes, including;

Failure of an antibiotic regimen (2)

2) Host factors

• poor host defense,

• age

• renal & liver function

• pre-existing dysfunction of other organs

3) Pathogen factors resistance superinfection

Antibiotic Resistance

“Penicillin Era” 1942-1950 available without a prescription1942-1950 available without a prescription Public demand followed by production of throat sprays, Public demand followed by production of throat sprays,

cough lozenges, mouthwashes, soaps and other products cough lozenges, mouthwashes, soaps and other products containing penicillincontaining penicillin

Alexander FlemingAlexander Fleming Warned that excessive use could result in antimicrobial Warned that excessive use could result in antimicrobial

resistanceresistance ““the microbes are educated to resist penicillin and a host the microbes are educated to resist penicillin and a host

of penicillin-fast organisms is bred out which can be of penicillin-fast organisms is bred out which can be passed to other individuals and from them to others until passed to other individuals and from them to others until they reach someone who gets a pneumonia or septicemia they reach someone who gets a pneumonia or septicemia which penicillin cannot savewhich penicillin cannot save.” The New York Times 1945.” The New York Times 1945

Fleming’s words proved to be correct....Fleming’s words proved to be correct....

The Problem of Antibiotic Resistance

Penicillin resistance first identified in Penicillin resistance first identified in 1940’s1940’s

Since then, antibiotic resistance has Since then, antibiotic resistance has developed faster than new drugsdeveloped faster than new drugs

Estimated cost of infections: $4-5 million Estimated cost of infections: $4-5 million per year per year

Antibiotic resistance previously Antibiotic resistance previously concentrated in hospitals, especially ICUsconcentrated in hospitals, especially ICUs

MRSA recently estimated to kill 18,000 MRSA recently estimated to kill 18,000 Americans yearlyAmericans yearly

History

APPEARANCE

DRUG INTRODUCTION OF RESISTANCE

Penicillin 1943 1946

Streptomycin 1945 1959

Tetracycline 1948 1953

Erythromycin 1952 1988

Vancomycin 1956 1988

Methicillin 1960 1961

Ampicillin 1961 1973

Cephalosporins 1964 late 1960’s

Antibiotic ResistanceRelative or complete lack of effect of

antimicrobial against a previously susceptible microbe

• Bacteria are said to be resistant to an antibiotic if the maximal level of that antibiotic that can be tolerated by the host does not stop their growth.

What causes the rapid occurrence of widespread resistance?

(1) Incomplete treatment:

- people fail to finish the full course of their medication

- 25% of previously-treated tuberculosis patients relapsed with drug resistant strains; most had failed to complete their initial course

What Factors Promote Antimicrobial Resistance?

(2) Mis-prescription:

- patients demand antibiotics for cold

- widespread inappropriate use: up to 50% of prescriptions in developing countries are for viral infections that cannot respond

What Factors Promote Antimicrobial Resistance?

(3) Exposure to microbes carrying resistance genes

Inappropriate Antibiotic Use

Prescription not taken correctlyPrescription not taken correctly Antibiotics for viral infectionsAntibiotics for viral infections Antibiotics sold without medical supervisionAntibiotics sold without medical supervision Spread of resistant microbes in hospitals Spread of resistant microbes in hospitals

due to lack of hygienedue to lack of hygiene Lack of quality control in manufacture or outdated Lack of quality control in manufacture or outdated

antimicrobialantimicrobial Use of broad-spectrum agents when a narrow-Use of broad-spectrum agents when a narrow-

spectrum drug would suffice spectrum drug would suffice (eg, use of third-generation cephalosporins for community-(eg, use of third-generation cephalosporins for community-

acquired pneumonia)acquired pneumonia)

• The four main mechanisms by which The four main mechanisms by which microorganisms exhibit resistance to antibiotics microorganisms exhibit resistance to antibiotics are:are:

(1) Drug inactivation or modification: e.g. enzymatic deactivation of Penicillin G in

some penicillin-resistant bacteria through the production of β-lactamases.

(2) Alteration of target site: e.g. alteration of PBP—the binding target site of

penicillins—in MRSA and other penicillin-resistant bacteria – resulting in decreased binding of the antibiotic to its target.

Mechanisms of Antibiotic Resistance (1)

(3) Alteration of metabolic pathway: e.g. some sulfonamide-resistant bacteria do not

require para-aminobenzoic acid (PABA), an important precursor for the synthesis of folic acid and nucleic acids in bacteria inhibited by sulfonamides. Instead, they turn to utilizing preformed folic acid.

(4) Reduced drug accumulation: by decreasing drug permeability and/or increasing active efflux (pumping out) of the

drugs across the cell surface.

Mechanisms of Antibiotic Resistance (2)

Resistance: -lactamase Enzymes

•Bacteria produce -lactamase enzymes to hydrolyze the -lactam ring before drugs can reach inner membrane where PG synthesis occurs

•A cell may produce 100,000 - lactamase enzymes, each of which can destroy 1,000 penicillins per second 100 million molecules of drug destroyed per second

• β-Lactam antibiotics act by inhibiting the synthesis of the peptidoglycan layer of bacterial cell walls.

-lactamases

Enzymes produced by bacteria which Enzymes produced by bacteria which destroy destroy -lactam antibiotics-lactam antibiotics

Many different typesMany different typesPenicillinases, cephalosporinases, Penicillinases, cephalosporinases,

carbapenemasescarbapenemases

Most are plasmid mediatedMost are plasmid mediated

Overcoming -lactam Resistance

slow tohydrolyze

As a response to bacterial resistance to -lactam drugs, there are drugs, such as Augmentin, which are designed to disable the -lactamase enzyme.

Augmentin is made of amoxicillin, a -lactam antibiotic, and clavulanic acid, a -lactamase inhibitor.

The clavulanic acid is designed to overwhelm all -lactamase enzymes, bind irreversibly to them, and effectively serve as an antagonist so that the amoxicillin is not affected by the -lactamase enzymes.

Amoxicillin (-lactam antibiotic)

+ clavulanic acid (a -lactamase inhibitor)

= Co-amoxiclav (Augmentin®)

Ampicillin (-lactam antibiotic)

+ sulbactam (a -lactamase inhibitor)

= Unasyn®

Overcoming -lactam Resistance

Genetic alterations in drug resistance

Acquired antibiotic resistance requires Acquired antibiotic resistance requires the temporary or permanent gain or the temporary or permanent gain or alteration of bacterial genetic alteration of bacterial genetic information.information.

Resistance develops due to the ability of Resistance develops due to the ability of DNA:-DNA:-

1.1. To undergo spontaneous mutationTo undergo spontaneous mutation

2.2. To move from one organism to another To move from one organism to another (DNA/gene transfer)(DNA/gene transfer)

Spontaneous mutation of DNA

Stable and heritable genetic change Not induced by antimicrobial agents Resistance variant will proliferate Eg. The emergence of rifampicin-resistant M.tuberculosis

when rifampicin is used as a single antibiotic

DNA/Gene transfer of drug resistant

transduction

conjugation

transformation

DNA Most resistance genes are plasmid mediated Plasmid may enter cells by processes such as conjugation,

transduction (phage mediated) & transformation

Measuring Antimicrobial Sensitivity

Disk DiffusionDisk Diffusion

E- test E- test (antimicrobial (antimicrobial gradient method)gradient method)

Serial dilutionSerial dilution

MIC increase in the case of resistance

(Minimal inhibitory concentration)

- important in diagnostic laboratories to confirm resistance of microorganisms to an antimicrobial agent

Measuring Antimicrobial Sensitivity

Consequences of Antimicrobial Resistance

Infections Infections resistant to resistant to available available antibioticsantibiotics

Increased cost Increased cost of treatmentof treatment

Speed development of new antibioticsTrack resistance data nationwideRestrict antimicrobial useNarrow spectrum Combination in long

term use (TB)Direct observed dosing (TB) Appropriate dose and duration Use more narrow spectrum antibioticsUse more narrow spectrum antibiotics Use antimicrobial cocktailsUse antimicrobial cocktails

Prevention of resistance

Pathogen Drug (s) of first choice Alternative Drug (s)

Gram +ve cocci PneumococcusPneumococcus Penicillin G, AmpicillinPenicillin G, Ampicillin Erythromycin, CephalosporinErythromycin, Cephalosporin

Streptococcus (common)Streptococcus (common) Penicillin GPenicillin G Erythromycin, CephalosporinErythromycin, Cephalosporin

Staphylococcus Staphylococcus

(penicillase-producing)(penicillase-producing)

AugmentinAugmentin®®, Unasyn, Unasyn®®, Cloxacillin, , Cloxacillin, Methicillin, Nafcillin, TimentinMethicillin, Nafcillin, Timentin®®

CephalosporinCephalosporin

Staphylococcus Staphylococcus

(methicillin resistance)(methicillin resistance)

VancomycinVancomycin TMZ-SMZTMZ-SMZ

EnterococcusEnterococcus Penicillin G plus gentamicinPenicillin G plus gentamicin Vancomycin plus gentamicinVancomycin plus gentamicin

Gram -ve cocci GonococcusGonococcus CetrriaxoneCetrriaxone Penicillin G, Ampicillin, Penicillin G, Ampicillin,

SpectinomycinSpectinomycin

MeningococcusMeningococcus Penicillin G, AmpicillinPenicillin G, Ampicillin Cefotaxime, Cefuroxime, Cefotaxime, Cefuroxime, ChloramphenicolChloramphenicol

Gram -ve rods E.coliE.coli, Proteus, Klebsiella, Proteus, Klebsiella Aminoglycosides, 3Aminoglycosides, 3rdrd generation generation

cephalosporincephalosporinTMZ-SMZ, Fluoroquinolone, TMZ-SMZ, Fluoroquinolone, extended spectrum penicillinextended spectrum penicillin

ShigellaShigella FluoroquinoloneFluoroquinolone TMZ-SMZ, AmpicillinTMZ-SMZ, Ampicillin

Enterobacter, Citrobacter,Enterobacter, Citrobacter,

SerratiaSerratia

Imipenam, FluoroquinoloneImipenam, Fluoroquinolone TMZ-SMZ, extended spectrum TMZ-SMZ, extended spectrum penicillinpenicillin

Hemophilus sppHemophilus spp Cefuroxime or 3Cefuroxime or 3rdrd generation generation cephalosporincephalosporin

TMZ-SMZ, Ampicillin,TMZ-SMZ, Ampicillin,

ChloramphenicolChloramphenicol

Pseudomonas aeruginosa Aminoglycosides plus extended Aminoglycosides plus extended spectrum penicillinspectrum penicillin

Ceftazidime, Aztreonam, ImipenamCeftazidime, Aztreonam, Imipenam

Bacteroides fragillis Metronidazole, ClindamycinMetronidazole, Clindamycin Imipenam, Chloramphenicol, Imipenam, Chloramphenicol, Ampicillin/sulbactamAmpicillin/sulbactam

RECOMMENDATIONSRECOMMENDATIONSDon'ts about antibiotics Don'ts about antibiotics DO NOTDO NOT...pressure your doctor to prescribe an ...pressure your doctor to prescribe an

antibiotic . antibiotic . DO NOTDO NOT...take antibiotics that have been sitting ...take antibiotics that have been sitting

around the house unless prescribed by your doctor for around the house unless prescribed by your doctor for a current illness . a current illness .

DO NOTDO NOT...give your antibiotics to other people.  Their ...give your antibiotics to other people.  Their illness is probably different than yours, and so your illness is probably different than yours, and so your antibiotics will not help them to get well.  Also, they antibiotics will not help them to get well.  Also, they might even be harmed by your medicine. might even be harmed by your medicine.

DO NOTDO NOT...take antibiotics simply because you were ...take antibiotics simply because you were exposed to someone with a disease.  You are only exposed to someone with a disease.  You are only increasing your chances of picking up a resistant increasing your chances of picking up a resistant infection.  If you are exposed to an infectious disease, infection.  If you are exposed to an infectious disease, seek medical adviceseek medical advice..

RECOMMENDATIONSRECOMMENDATIONS

Do's about antibiotics Do's about antibiotics DODO...ask your doctor whether your infection or your ...ask your doctor whether your infection or your

family member's infection will respond to antibiotics. family member's infection will respond to antibiotics. DODO...ask your doctor about antibiotic-resistant bacteria ...ask your doctor about antibiotic-resistant bacteria

and what you can do to help prevent its occurrence. . and what you can do to help prevent its occurrence. . DODO...follow the instructions for taking your antibiotic.  ...follow the instructions for taking your antibiotic. 

Always take the exact amount specified on the label at Always take the exact amount specified on the label at a specified time.  Take the medicine for the entire time a specified time.  Take the medicine for the entire time that your doctor has prescribed.  Even if you feel that your doctor has prescribed.  Even if you feel better, take all of the medicine!better, take all of the medicine!