Pharm Exam 4: Antibiotics

UNM NMNC 3230: Nursing Pharmacology

Penicillin

ex: amoxicillin (-cillin)

I: Staph, Strep, Enterococcus

• Lots of resistance, allergies, cross-hypersensitivity

MoA: Bactericidal (Interferes with cell wall formation)

ADR: GI upset, rash, yeast infection

Cephalosporins

Ex: Cefazolin (-cef/-ceph)

MoA: Bactericidal (Interferes with cell wall formation)

ADR: Diarrhea

• allergy (PCN too)

Glycopeptides

Ex: Vancomycin

MoA: Bactericidal (Binds to cell wall causing immediate death)

I: Treatment of choice for MRSA (IV)

• Given orally for C. Diff

ADR: Red Man syndrome, Ototoxicity, Nephrotoxicity, thrombophlebitis

• Infuse slowly over 60 minutes or more

Peak + Trough

Tetracyclines

Ex: Tetracycline (-cycline)

MoA: Bacteriostatic (Inhibit bacterial protein synthesis)

ADR: Discoloration of permanent teeth, inhibits tooth and skeletal formation in fetus, Photosensitivity, Diarrhea

CI: Allergy, Pregnant women, Children under 8 years, warfarin, other antibiotics, antacids, dairy, iron supplements,tub feeding

On an empty stomach, lots of water

Macrolides

Ex: Azithromycin (-mycin)

MoA: Bacteriostatic, can be bactericidal in high doses to some bacteria

• Bind to bacterial ribosomes and inhibit protein synthesis

ADR: GI upset, transient hearing loss & vertigo, hepatotoxicity, QT prolongation

Drug interactions: Highly protein bound

On empty stomach

Aminoglycosides

Ex: Gentamicin (-mycin/-micin)

MoA: Bactericidal (Bind to ribosomes and prevent protein synthesis)

Once a day dosing 

Work best when combined with other antibiotics

ADR: Nephrotoxicity, Ototoxicity,

Quinolones

Ex: Ciprofloxacin (-flox-)

MoA: Bactericidal (alter bacterial DNA)

ADR: ruptured tendons and tendinitis, Peripheral neuropathy, Seizures, Liver injury, Photosensitivity

IV: Infuse slowly over at least 60 minutes

PO: take antacids, iron & calcium supplements, dairy products 2 hours after or 6 hours before ciprofloxacin

Sulfonamides

Ex: Sulfamethoxazole-Trimethoprim (Sulfa-)

MoA: Bacteriostatic (Inhibit bacterial growth by preventing bacterial folic acid)

CI:Allergy, pregnancy + infants

ADR: Rash + Steven Johnsons syndrome, photosensitivity, photosensitivity, Immune mediated reactions in other organs, GI upset and diarrhea, Crystalluria

Urinary Tract Antiseptics

Ex: Nitrofurantoin

MoA: bactericidal or bacteriostatic (only work in urinary tract)

ADR: red/brown discoloration of urine, dizziness, drowsiness, headache, photosensitivity

• hypersensitivity: dyspnea, chest pain, chills & cough, pulmonary fibrosis

Admin: take w/ food to minimize GI distress, do not take with pregnancy

Antibiotic Patient Teaching

Take antibiotics exactly as instructed-DO NOT skip or double up

• Give antibiotics within 30 minutes of time due

• Watch peak and trough

Report any rash or allergic symptoms

Use backup birth control method

Do NOT drink alcohol

• Check renal and hepatic function (liver enzyme)

Cause diarrhea

Isoniazid (INH)

Antimycobacterial

I: given alone for prophylaxis or in combo for treatment of TB

MoA: Bactericidal

ADR: Can be toxic to liver or cause hepatitis, Peripheral neuropathy, Visual disturbances

Supplement vitamin B-6

Treatment is 6-9 months (or longer)

Rifampin

Class: broad spectrum antibiotic

I: TB, Legionnaire’s ds., meningococcal meningitis

MoA: inhibits RNA polymerase, suppresses protein synthesis

ADR: GI Effects, Hepatotoxicity/ Hepatitis (no alcohol), Orange/red discoloration of urine, sweat, saliva, tears, rash, itching, flushing

Drug Interactions:

• other anti-TB drugs- increase hepatotoxicity risk

• monitor LFT’s, s/s hepatic disease

Antifungal Drugs

Ex: Miconazole (topical)

I: Athlete's foot, vaginal yeast infections, other skin infections

MoA: Inhibit fungal growth by affecting fungal cellular metabolism

ADR: itching burning after application

OTC - cream or vaginal suppository (2-4 wks)

Antiviral Drugs

Ex: Acyclovir

I: HSV, varicella (chickenpox), and herpes zoster (shingles)

MoA: inhibits viral replication of DNA

ADR: N/V, GI distress, headache, vertigo, renal toxicity, CNS toxicity

Check BUN/SCr, check patency of IV before infusion, keep client hydrated