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Chapter 12Antiinfective Medications

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Action of AntimicrobialsHuman tissue

Before treatment with

antimicrobial drugs

Human tissue After treatment with antimicrobial drugs (tissue remains the same, microbes have been destroyed)

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Antibiotics

• Broad-spectrum

• Narrow-spectrum

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Penicillins commonly end in “cillin”

• Largest most effective and least toxic

• Penicillin-resistant strains• Broad-spectrum drug of choice

SUPER Germ!

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Penicillins (cont.)

Action and Uses• Inhibit Cell wall synthesis• Used to treat multiple infections

(syphilis, wound infections,prophylaxis for endocarditis)

• Overuse and allergies

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Penicillins (cont.)

Adverse Reactions • Neuropathy

– High parenteral doses• Skin eruptions• GI symptoms• Urticaria• Laryngeal edema• Anaphylaxis

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Probenecid prolongs blood levels by blocking PCN’s renal clearance

Hold it right there Penicillin!! You

ain’t goin no where!

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Penicillins (cont.)

Nursing Implications and PatientTeaching

• Assessment– Signs of infection and allergies

• Planning– 10-day regimen

– cultures should be drawn prior to starting antibiotic therapy

– What happens if pcn is not given in effective doses or for the length of time required?

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Sulfonamides root has “sulf” in name

• Broad-spectrum antiinfective

• Bacteriostatic action

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Sulfonamides (cont.)

Action and Uses • Urinary tract infections• Preoperative and postoperative therapy

for bowel surgery• treats PCP, meningococcal meningitis,

ulcerative colitis...• What is a superinfection??

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Sulfonamides (cont.)

Adverse Reactions• Crystaluria• toxemia• fever

Teaching• drink adequate fluids (promote urinary

output to 1500ml/day)

• take on empty stomach

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What is the normal BUN and CR levels?

BUN level = 5-25mg/dLCR=0.5-1.5mg/dL

It only takes 0.5-1.5 hours to CReate 5-25 BUNs in the oven

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Amnioglycosidesall end in “mycin” (not all that end in mycin are aminoglycosides.)

• Strong antimicrobial Bactericidal drugs reserved for life threatining infections

• Gentamycin (garamycin)• Amikacin (Amikin)• Tobramycin (Nebcin)

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Aminoglycosides cont..Side effects• nephrotoxicity and ototoxicityNursing Considerations

– monitor Peak and Trough Levels– prior to therapy what should the nurse do?– Monitor …– Premedicate with anti-emetics,

antihistamines and corticosteroids to decrease side effects

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Broad-Spectrum Antibiotics • Bactericidal or bacteriostatic

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Broad-Spectrum Antibiotics (cont.)

Action and Uses • Large number of unrelated drugs used

to treat infections caused by susceptible organisms

• Gram-positive or gram-negative organisms

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Broad-Spectrum Antibiotics (cont.)

Adverse Reactions

• Superinfections• Drug interactions are individualized• Food interactions• Affected organs: auditory nerves,

kidneys, and liver• Cross-sensitivity

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Learning Objectives

• Identify the major antiinfective drug categories and the organisms against which they are effective

• Outline the most important things to teach the patient who is taking antiinfective drugs

• List some of the most common adverse reactions to medications used to treat infections

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Tuberculosis

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Antitubercular Drugs

What does MDR refer to? Multiple Drug Resistant Organisms

What role does the CDC have in relation to Tuberculosis treatment?

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Antitubercular Drugs

• Isoniazid (INH,Nydrazid)• Rifampin (Rifadin, Rimactane)• Rifabutin (Mycobutin)

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Antitubercular Drugs (cont.)

Action and Uses • Most antitubercular drugs are

bacteriostatic, (some bacterialcidal)• INH (Isoniazid) only drug

recommended for prophylactic therapy.

• What is the current duration of prophylactic treatment?

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Antitubercular Drugs (cont.)Adverse Reactions • Common symptoms• Toxicity: body sights affected• Combination therapy• Drug-specific symptoms

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• Why are combination drugs used in the treatment of tuberculosis?

• What are the most common side effects of Antitubercular drugs?

• What are the typical s/s of active TB?

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Which statement by the patient indicates that he has an accurate understanding of the functioning of an antiviral medication?• A."If I take this medication correctly, my

viral infection will not reoccur.“• B."If this medication is not effective, I can

take an antibiotic medication instead.“• C."If I take the medication, my symptoms

will lessen and the infection will be cured.“• D."I should not expect the medication to

cure my disease, but symptoms will decrease."

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Antiparasitic Drugs

• Amebicides

• Anthelmintics

• Antimalarials

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Amebicides Chloroquine (Aralen)Metronidazole (Flagyl, Metrogel)

• Caused by the parasite E”ntamoeba histolytica”

• Relationship to traveling

• Infection sights in the body– GI or extraintestinal

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Amebicides (cont.)

Action and Uses • Destroy invading ameba• Treatment of intestinal and

extraintestinal amebiasis.• Drug choice depends on location

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Amebicides (cont.)

Adverse Reactions • Common: nausea, vomiting, anorexia,

diarrhea, GI distress, hepatic abscess• Drug-specific adverse reactions

– Flagyl:ECG changes, ataxia, confusion, blurry vision, nasal congestion, dysuria

• Overdose

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Random questions...

• What are superinfections?

• Pseudomembranos colitis is caused by which bacteria?

• How does it manifest?

• How is it treated?

• What are the expected therapeutic effects of antibiotics?

• How long are PCNs usually prescribed for?

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HIV Infection

Acquired immunodeficiency syndrome (AIDS)– Viral disease– High mortality rate

High-risk populations include:– Homosexual and bisexual men– Intravenous drug users– People in prison – Female sexual partners of people in high-risk

groups– Children born to mothers at risk

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Antivirals

Action and Uses • Decrease symptoms of viral infection• Lessen the symptoms of viral illness in

immunocompromised patients or adults and children at risk

Adverse Reactions– Hepatotoxicity, nephrotoxicity, blood

dyscrasias, peripheral neuropathies

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Antivirals (cont.)

Nursing Implications and Patient Teaching

• Medications do not cure• Follow specific storage instructions• Reporting adverse reactions• Administration

– Encourage immunocompromised clients in areas with impure water supplies to drink bottled water only

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Antiretrovirals

Action• Interfere with the ability of a retrovirus

to reproduce or replicate• Two types:

– Reverse transcriptase inhibitors• Act early in viral life cycle

– Protease inhibitors• Act later in viral life cycle

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Antiretrovirals (cont.)

Uses– Slow advance of AIDS– Maintain immunity– Prevention of HIV in infants born to

HIV-infected mothers– Prevention of HIV in healthcare

workers exposed to HIV

Drug Interactions

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Antiretrovirals (cont.)

Nursing Implications and Patient Teaching

• Adherence is essential• Medications do not cure• Report all drugs and supplements used,

including OTC and CAM• Signs and symptoms of pancreatitis• Signs and symptoms of peripheral

neuropathy

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Antiretrovirals (cont.)

Nursing Implications and Patient Teaching

(cont.)• Routes of disease transmission• Need for social and financial support

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Antifungals

Action– Fungistatic– Fungicidal

Uses– Treat mycotic infections

• Fungal-specific medications• Systemic medications

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Antifungals (cont.)

Common Antifungal Medications:Ketoconazole (Nizoral)

• Broad-spectrum fungistatic and fungicidal action

• Used to treat oral thrush, candidiasis, histoplasmosis

Nystatin (Mycostatin)• Antibiotic with fungistatic and fungicidal action• Used to treat intestinal, vaginal, and oral fungal

infections caused by Candida strains

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Antifungals (cont.)

Common Antifungal Medications (cont.)Amphotericin B (Amphotec)

• Systemic drug

Griseofulvin• Activity decreased with barbiturates

Metronidazole (Flagyl)• Related drug for mixed fungal and bacterial or

protozoa infections; interacts with alcohol

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Antifungals (cont.)

Nursing Implications and Patient Teaching• Take all the medication as ordered; do not stop

when symptoms disappear• Avoid alcohol• Report nausea, vomiting, and diarrhea; watch for

easy bruising, sore throat, rash, or fever• Nystatin must be shaken thoroughly before use• Intolerance to the sun (photosensitivity) can

occur with griseofulvin therapy• Cleanliness of hair, skin and nails will limit spread