Gentamicin (Garamycin) Injection


  • Antibiotic


  • Aminoglycoside antibiotic


  • Serious infections (P. aeruginosa, Proteus species, E. coli, Klebsiella species, Enterobacter species, Serratia species, Citrobacter species, Staphylococcus species)

  • Bacterial neonatal sepsis

  • Bacterial septicemia

  • Serious bacterial infections of the CNS (meningitis)

  • Urinary tract, respiratory tract, skin, bone and soft tissue (including burns) infections

  • Gram-negative infections

  • Emperic therapy for unknown serious infections


  • Generally not indicated for long-term therapy due to nephrotoxocity and ototoxicity


  • Pregnancy category D

  • May cause nephrotoxicity, therefore closely monitor renal function, especially in elderly patients.

  • May cause ototoxicity, therefore monitor hearing

  • Monitor peak and trough serum concentrations

  • In patients with extensive burns, altered pharmacokinetics may alter serum concentrations.

  • May produce hypomagnesemia, especially if poor or restricted diet.

  • Aminoglycosides have neuromuscular blockade activity with a curare-like effect.  Monitor patientís neuromuscular function, especially in patients with myasthenia gravis, parkinsonism or infant botulism.

Adverse Reactions (Side Effects):

  • Central and peripheral nervous system reactions:

    • Headache

    • Depression

    • Confusion

    • Lethargy

    • Muscle twitching

    • Peripheral neuropathy

  • Gastrointestinal: vomiting, nausea, anorexia, hypersalivation

  • Hematologic: changes in reticulocyte counts, anemia, altered WBC counts

  • Hypersensitivity: rash, urticaria, itching

  • Special senses: dizziness, tinnitis, vertigo

  • Renal: oliguria, proteinuria, increased creatinine and BUN

  • Miscellaneous: apnea, alopecia, joint pain

  • Pain at injection site

  • Decreased calcium, sodium, potassium and magnesium levels  


  • Administered by IM or IV injection

  • Therapy duration is generally 7-10 days

Adults: normal renal function: 3mg/kg/day IV or IM in 3 equal doses every 8 hours
Q8 hour Dose (Moderate Infections)
132 60 60 mg IM/IV
154 70 70 mg IM/IV
176 80 80 mg IM/IV
198 90 90 mg IM/IV

Serious infections: 5mg/kg/day divided into 3-4 equal doses
Q8 hour Dose (Serious Infections)
132 60 100 mg IM/IV
154 70 117 mg IM/IV
176 80 133 mg IM/IV
198 90 150 mg IM/IV
  • obese patients: 

    • base dose on lean body mass

  • Children:

    • 6-7.5mg/kg/day (2-2.5mg/kg q8h)

  • Infants and neonates

    • 7.5mg/kg/day (2.5mg/kg q8h)

  • Premature or full term neonates (< 1 week of age):

    • 5mg/kg/day (2.5mgkg q12h)

Back to Medical Corps Pharmacy Page