Last reviewed 2026-04-20 · How we verify

Gentamicin (Gentamicin Sulfate)

Gentamicin is an aminoglycoside antibiotic indicated for serious infections caused by susceptible gram-negative and gram-positive bacteria. Peak serum concentrations occur 30-60 minutes after IM administration with measurable levels for 6-8 hours; dosing must be adjusted in renal impairment. Contraindicated in patients with hypersensitivity to gentamicin or other aminoglycosides due to cross-sensitivity risk. Use should be guided by culture and susceptibility testing to reduce resistance development and minimize toxicity potential.

At a glance

Approved indications

• Bacterial conjunctivitis
• Bacterial infection due to Klebsiella pneumoniae
• Bacterial infection due to Serratia
• Bacterial infection of skin
• Bacterial keratitis
• Bacterial meningitis
• Bacterial pneumonia
• Bacterial septicemia
• Blepharoconjunctivitis
• Burn Wound Infections
• Cholangitis
• Citrobacter Pneumonia
• Citrobacter Septicemia
• Complicated Bacterial Peritonitis
• Complicated UTI with Pseudomonas Aeruginosa
• Complicated Urinary Tract Infections
• Dacryocystitis
• Enterobacter Pneumonia
• Folliculitis
• Furunculosis

Boxed warnings

• BOXED WARNINGS Patients treated with aminoglycosides should be under close clinical observation because of the potential toxicity associated with their use. As with other aminoglycosides, gentamicin injection is potentially nephrotoxic. The risk of nephrotoxicity is greater in patients with impaired renal function and in those who receive high dosage of prolonged therapy. Neurotoxicity manifested by ototoxicity, both vestibular and auditory, can occur in patients treated with gentamicin, primarily in those with pre-existing renal damage and in patients with normal renal function treated with higher doses and/or for longer periods than recommended. Aminoglycoside-induced ototoxicity is usually irreversible. Other manifestations of neurotoxicity may include numbness, skin tingling, muscle twitching and convulsions. Renal and eighth cranial nerve function should be closely monitored, especially in patients with known or suspected reduced renal function at onset of therapy and also in those whose renal function is initially normal but who develop signs of renal dysfunction during therapy. Urine should be examined for decreased specific gravity, increased excretion of protein and the presence of cells or casts. Blood urea nitrogen (BUN), serum creatinine or creatinine clearance should be determined periodically. When feasible, it is recommended that serial audiograms be obtained in patients old enough to be tested, particularly high-risk patients. Evidence of ototoxicity (dizziness, vertigo, tinnitus, roaring in the ears or hearing loss) or nephrotoxicity requires dosage adjustment or discontinuance of the drug. As with the other aminoglycosides, on rare occasions changes in renal and eighth cranial nerve function may not become manifest until soon after completion of therapy. Serum concentrations of aminoglycosides should be monitored when feasible to assure adequate levels and to avoid potentially toxic levels. When monitoring gentamicin peak concentrations, dosage should be adjusted so that prolonged levels above 12 mcg/mL are avoided. When monitoring gentamicin trough concentrations, dosage should be adjusted so that levels above 2 mcg/mL are avoided. Excessive peak and/or trough serum concentrations of aminoglycosides may increase the risk of renal and eighth cranial nerve toxicity. In the event of overdosage or toxic reactions, hemodialysis may aid in the removal of gentamicin from the blood, especially if renal function is, or becomes, compromised. The rate of removal of gentamicin is considerably lower by peritoneal dialysis than it is by hemodialysis. In the newborn infant, exchange transfusions may also be considered. Concurrent and/or sequential systemic or topical use of other potentially neurotoxic and/or nephrotoxic drugs, such as cisplatin, cephaloridine, kanamycin, amikacin, neomycin, polymyxin B, colistin, paromomycin, streptomycin, tobramycin, vancomycin and viomycin, should be avoided. Other factors which may increase patient risk of toxicity are advanced age and dehydration. The concurrent use of gentamicin with potent diuretics, such as ethacrynic acid or furosemide, should be avoided, since certain diuretics by themselves may cause ototoxicity. In addition, when administered intravenously, diuretics may enhance aminoglycoside toxicity by altering the antibiotic concentration in serum and tissue. Aminoglycosides can cause fetal harm when administered to a pregnant woman (see WARNINGS section).

Common side effects

• Nephrotoxicity
• Hearing loss
• Dizziness
• Vertigo
• Tinnitus
• Roaring in the ears
• Nausea
• Vomiting
• Respiratory depression
• Lethargy
• Confusion
• Depression

Drug interactions

• cisatracurium
• metocurine
• mezlocillin
• mivacurium
• pancuronium
• pentamidine
• pipecuronium
• piperacillin
• rocuronium
• suxamethonium
• ticarcillin
• torsemide

Key clinical trials

• Retrospective Simplex High Viscosity (HV) Bone Cement Study
• Irrisept vs Traditional Antibiotic Irrigation for Virgin Penile Prosthesis Placement (PHASE3)
• Intramedullary Calcium Sulfate Antibiotic Depot (PHASE3)
• Gentamicin Bladder Instillation in Individuals With Spinal Cord Injury Having Chronic Urinary Tract Infections (PHASE2)
• A Study to Compare Different Antibiotics and Different Modes of Fluid Treatment for Children With Severe Pneumonia (PHASE3)
• Gentamicin Bladder Instillations to Prevent Urinary Tract Infections in Patients With Spinal Cord Injury (PHASE2, PHASE3)
• Hydrocolloid Dressing for Catheter Exit Site Care in Peritoneal Dialysis Patients (NA)
• The Safety and Efficacy of Addition of Gentamicin on Irrigation Fluid in Prevention of Post-Transurethral Resection of the Prostate Infectious Complications. (NA)

Primary sources

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Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Gentamicin CI brief — competitive landscape report
• Gentamicin updates RSS · CI watch RSS
• Merck & Co. portfolio CI