Iv%252525252525252520gentamicin

# IV Gentamicin ## Overview Gentamicin is an aminoglycoside antibiotic that inhibits bacterial protein synthesis by binding to the 30S ribosomal subunit. It exhibits concentration-dependent bactericidal activity and a significant post-antibiotic effect. ## Primary Indications * Serious Gram-negative infections (e.g., *Pseudomonas aeruginosa*, *Enterobacteriaceae*). * Synergistic treatment for Gram-positive endocarditis (e.g., *Enterococcus*, *Staphylococcus*). * Empiric treatment of neonatal sepsis. ## Adult Dosing * **Traditional (Multiple-Daily) Dosing:** 1.5–2.5 mg/kg IV every 8 to 12 hours. * **Extended-Interval (Once-Daily) Dosing:** 5–7 mg/kg IV every 24 hours (based on renal function and nomograms like Hartford). * **Synergy Dosing (Endocarditis):** 1 mg/kg IV every 8 hours (usually limited to 3-5 mg/kg/day total). * *Note: Dosing must be based on Ideal Body Weight (IBW) if patient is obese; if actual weight is less than IBW, use actual weight.* ## Pediatric Dosing * **Neonates (0-7 days):** 2.5–5 mg/kg/dose every 12–24 hours, depending on gestational age and weight. * **Infants/Children/Adolescents:** 2.5 mg/kg/dose IV every 8 hours (traditional). * *Note: Many institutions utilize weight-based extended-interval protocols for pediatrics (e.g., 5–7.5 mg/kg every 24–48 hours); verify local institutional policy.* ## Dose Adjustments * **Renal Impairment:** Required. Dose must be adjusted based on creatinine clearance (CrCl) or serum concentrations. * **Obesity:** Use adjusted body weight (AdjBW) if Total Body Weight > 20% over IBW. ## Contraindications * Hypersensitivity to aminoglycosides. * History of severe reactions to other aminoglycosides. ## Adverse Effects * **Nephrotoxicity:** Typically reversible; associated with trough accumulation. * **Ototoxicity:** Vestibular (vertigo/ataxia) or auditory (tinnitus/hearing loss); often permanent. * **Neuromuscular Blockade:** Rare, usually associated with rapid infusion or excessive doses. ## Key Drug Interactions * **Nephrotoxic Agents:** Increased risk with vancomycin, amphotericin B, NSAIDs, IV contrast, and cisplatin. * **Ototoxic Agents:** Increased risk with loop diuretics (e.g., furosemide). * **Neuromuscular Blocking Agents:** Potential for additive paralytic effect. ## Monitoring * **Serum Concentrations:** Obtain random levels for extended-interval dosing (e.g., 6–14 hours post-dose per Hartford nomogram) or peaks/troughs for traditional dosing. * **Renal Function:** Monitor Serum Creatinine and BUN at baseline and periodically during therapy. * **Clinical:** Monitor for signs of ototoxicity (dizziness, baseline hearing changes). ## Clinical Pearls * **Dosing Weight:** Improper weight-based dosing is a common source of medication errors. Always confirm whether your protocol uses IBW or AdjBW. * **Administration:** Infuse over 30–60 minutes. * **Synergy:** When used for synergy in endocarditis, therapeutic drug monitoring is focused on maintaining safe troughs rather than achieving high peaks. *** *Disclaimer: This information is for educational purposes only. Dosing protocols vary significantly by institution and patient variables. Always verify current prescribing information, institutional guidelines, and regional susceptibility patterns before initiating therapy.*