Iv%252525252525252525252525252525252525252525252525252520gentamicin

# IV Gentamicin ## Overview Gentamicin is an aminoglycoside antibiotic that exerts bactericidal activity by irreversibly binding to the 30S ribosomal subunit, inhibiting bacterial protein synthesis. It provides excellent coverage against aerobic gram-negative bacilli, including *Pseudomonas aeruginosa*. ## Primary Indications * Serious systemic infections (e.g., sepsis, complicated intra-abdominal infections, pyelonephritis). * Synergistic treatment for gram-positive endocarditis (when combined with beta-lactams or vancomycin). * Prophylaxis or treatment of neonatal sepsis. ## Adult Dosing * **Traditional Dosing:** 3–5 mg/kg/day divided every 8 hours. * **Extended-Interval (Once-Daily) Dosing:** 5–7 mg/kg administered once every 24 hours (based on renal function). * **Endocarditis Synergy:** 1 mg/kg every 8 hours. * *Note: Always consult local institutional protocols, as nomograms (e.g., Hartford Nomogram) dictate specific intervals based on serum concentrations.* ## Pediatric Dosing * **Neonatal (0–7 days):** 2.5–4 mg/kg every 12–24 hours (weight/gestational age dependent). * **Infants/Children:** 2.5 mg/kg every 8 hours (traditional) or 5–7.5 mg/kg every 24 hours (extended-interval). * *Note: Dosing is highly weight-based; neonatal dosing requires strict adherence to institutional weight-based guidelines.* ## Dose Adjustments * **Renal Impairment:** Required. Dose reduction or interval extension is mandatory for CrCl < 60 mL/min. Use ideal body weight (IBW) for dosing if the patient is obese to minimize toxicity. * **Obesity:** Use adjusted body weight (AdjBW) if TBW > 120% of IBW. ## Contraindications * Hypersensitivity to gentamicin or other aminoglycosides. * Use with caution in patients with myasthenia gravis or neuromuscular blockade, as aminoglycosides may exacerbate weakness. ## Adverse Effects * **Nephrotoxicity:** Usually reversible; associated with high trough levels. * **Ototoxicity:** Irreversible; manifests as vestibular damage or cochlear damage (hearing loss). * **Neurotoxicity:** Peripheral neuropathy or neuromuscular blockade (rare, associated with rapid infusion or high doses). ## Key Drug Interactions * **Nephrotoxic agents:** Increased risk of renal failure with concurrent cisplatin, amphotericin B, vancomycin, or NSAIDs. * **Neuromuscular Blockers:** Potentiation of paralytic effects. * **Loop Diuretics:** Increased risk of ototoxicity (e.g., furosemide). ## Monitoring * **Serum Concentrations:** Required for most patients. * *Traditional:* Measure peak (30 min post-infusion) and trough (immediately pre-dose). * *Extended-Interval:* Measure random level at 6–14 hours post-infusion using a nomogram. * **Renal Function:** Monitor serum creatinine and BUN daily. * **Auditory/Vestibular:** Monitor for symptoms of tinnitus, vertigo, or hearing loss. ## Clinical Pearls * **Avoid "Peak" Toxicity:** Gentamicin exhibits concentration-dependent killing; ensure adequate peaks for efficacy, but maintain low troughs to prevent accumulation-related toxicity. * **Volume of Distribution:** Aminoglycosides are hydrophilic; dehydration or extracellular fluid expansion (e.g., edema, burns) shifts drug distribution and necessitates dose recalibration. * **Infusion:** Administer over 30–60 minutes to avoid rapid fluctuations in serum concentration. *** **Educational Disclaimer:** This information is clinical guidance. Always verify dosages, contraindications, and monitoring requirements against your institution's specific pharmacy protocols and the most recent package insert before prescribing or administering medication.