Gentamicin
GARAMYCIN
What it isAminoglycoside inhibiting the 30S ribosome; serious Gram-negative infection and combination therapy for endocarditis.
Why this oneAmong aminoglycosides, it is the standard partner for Gram-positive endocarditis synergy.
What limits itMonitor levels and renal function: nephrotoxicity is often reversible, but vestibular or auditory damage may not be.
FDA-approved for
- Gram-negative infections (1971)
FDA label
Read the full label on DailyMed ↗
| FDA dosing | Population | Start | Target | Max |
|---|---|---|---|---|
| Serious bacterial infection | Adults, normal renal function | 3 mg/kg/day divided q8h | 3 mg/kg/day q8h | 5 mg/kg/day (life-threatening; 3–4 divided doses) |
| Serious bacterial infection | Children | 6–7.5 mg/kg/day (2–2.5 mg/kg q8h) | ||
| Serious bacterial infection | Infants/neonates | 7.5 mg/kg/day (2.5 mg/kg q8h) | ||
| Serious bacterial infection | Neonates ≤1 wk / premature | 5 mg/kg/day (2.5 mg/kg q12h) |
Renal Reduce dose or extend dosing interval in renal impairment; monitor peak and trough serum levels
Hepatic Undefined
Instructions
- Give IM or by IV infusion
- Dose on lean body mass in obesity
- Monitor peak (4–6 mcg/mL) and trough (<2 mcg/mL); avoid prolonged peaks >12 mcg/mL
- Usual duration 7–10 days
Contraindications
- History of hypersensitivity or serious toxic reaction to other aminoglycosides (cross-sensitivity)
Cautions
- Nephrotoxicity — casts/proteinuria, rising BUN/creatinine
- Neurotoxicity — ototoxicity (vestibular/auditory, may be irreversible)
- Peripheral neuropathy/encephalopathy, neuromuscular effects
- Higher risk with renal impairment, dehydration, prior ototoxic exposure
Adverse reactions
- Nephrotoxicity
- Ototoxicity (dizziness, vertigo, tinnitus, hearing loss)
- Peripheral neuropathy
- Rash/urticaria
- Nausea/vomiting
Pregnancy Aminoglycosides can cause fetal harm (see Warnings)
Lactation Undefined
⚠ BOXED WARNINGS
- Nephrotoxicity and ototoxicity
- Neuromuscular blockade
Cost, est. cash$10–$500/month
Generic entryPre-1982
Classes and tags
Clinical profile
Legacy pregnancy categoryD
Defining liabilityNephrotoxicity and often irreversible ototoxicity require renal and concentration monitoring.
Mechanism of action: Gentamicin ballicule
