Overview
This lecture covers essential antibiotics and anti-infectives, focusing on their mechanisms, side effects, contraindications, and key test tips for nursing exams.
Top 6 Test Tips for Antibiotics
- Always finish the full course to prevent superinfection and superbugs.
- Penicillins and tetracyclines reduce oral contraceptive effectiveness; use additional contraception.
- Avoid alcohol with antibiotics due to liver toxicity risk.
- Take macrolides, tetracyclines, and fluoroquinolones on an empty stomach with water.
- Avoid sun for fluoroquinolones, tetracyclines, and sulfa drugs due to photosensitivity.
- "Mycin"/aminoglycosides (gentamicin, vancomycin) are nephrotoxic and ototoxic; monitor for toxicity.
Broad-Spectrum Antibiotics: Penicillins & Cephalosporins
- Mechanism: Destroy bacterial cell wall.
- Both are pregnancy and breastfeeding safe.
- Penicillins can cause accidental pregnancy—use backup contraception.
- Cephalosporins do NOT treat C. diff infections.
- Check for cross-sensitivity; allergies to one may mean allergy to the other.
- In case of allergy: stop med, assess reaction, listen to lungs, prepare epinephrine.
Toxic Antibiotics: Aminoglycosides & Glycopeptides
- Examples: gentamicin, tobramycin, vancomycin.
- Monitor peaks and troughs (therapeutic: 10-20).
- Signs of toxicity: vertigo, tinnitus, rising creatinine (>1.3), BUN (>20), urine output <30 ml/hr.
- Vancomycin can cause "red man syndrome" from rapid infusion; slow infusion, monitor BP.
- Aminoglycosides are risky in elderly and those with renal issues.
Other Major Antibiotics
- Macrolides (azithromycin, erythromycin): Risk for prolonged QT, hepatotoxicity—monitor ECG and liver labs.
- Tetracyclines (doxycycline): Not pregnancy safe, causes tooth discoloration and sunburn, avoid dairy/antacids/iron, sit up 30 min after taking.
- Metronidazole (Flagyl): Treats C. diff and STIs; avoid alcohol; normal: dark urine, metallic taste; report any rash.
UTI Medications
- Sulfonamides (Bactrim): Photosensitivity, kidney stones (urine crystals), not pregnancy safe, drink 2-3L water/day.
- Fluoroquinolones (levofloxacin): Avoid sun, risk of Achilles tendon rupture; not highly nephrotoxic.
- Phenazopyridine (Pyridium): Urinary analgesic, turns urine orange/red, can cause jaundice—report yellow skin/eyes.
Key Terms & Definitions
- Ototoxicity — toxic effect on the ear/hearing.
- Nephrotoxicity — toxic effect on the kidneys.
- Photosensitivity — increased sensitivity to sunlight.
- Red man syndrome — flushing and hypotension from rapid vancomycin infusion.
- Anaphylaxis — severe allergic reaction with respiratory distress and hives.
Action Items / Next Steps
- Review patient allergies before antibiotic administration.
- Teach patients to finish full antibiotic courses.
- Monitor key labs (creatinine, BUN, liver enzymes) and report significant changes.
- Counsel patients on contraception, sun exposure, and alcohol avoidance as appropriate.
- Complete readings on antibiotic classes and their clinical uses.