Are you a Health Professional? Jump over to the doctors only platform. Click Here

Gentamicin Injection BP

Generic Name: Gentamicin sulfate
Product Name: Gentamicin Injection BP


Gentamicin is used for the treatment of infections caused by susceptible organisms (see Action Description for full list of bacteria). These conditions include:

  • Blood infection.
  • Respiratory tract infections.
  • Urinary tract infection.
  • Skin and skin structure infections.
  • Bone and joint infections.
  • Peritonitis.
  • Septic abortion.
  • Burns complicated by sepsis.

Gentamicin is not the first-line treatment for uncomplicated urinary tract infections, unless the causative organism has been shown to be resistant to other less toxic antibiotics.

In the treatment of any infection, it is important to isolate the bacteria and its antibacterial susceptibilities if possible before commencing treatment.



Gentamicin is a bactericidal antibiotic, which means it kills bacteria rather than just stopping their replication. It acts by inhibiting protein synthesis, a vital process for bacterial survival. It is active against a wide range of Gram-negative bacteria (many famous for causing urinary tract infections) including E coli. It is also active against the dangerous bug Pseudomonas aeruginosa, which is difficult to treat.

Gentamicin also has activity against Salmonella and Shigella species responsible for food poisoning.

Gentamicin is active against Staphylococcus aureus (also known as Golden Staph) including Methicillin resistant Staphylococcus Aureus (MRSA).

Dose advice

Each ampule is for use in one patient on one occasion only. Gentamicin is generally given as an intramuscular injection, after which it is quickly absorbed into the bloodstream. Intravenous administration is possible where intramuscular injection is inappropriate, and identical doses are used.


Serious urinary tract and systemic infections:

  • 3mg/kg/day in three doses given every 8 hours.Life threatening infections:
  • 5mg/kg/day in three or four equal doses.
  • Reduce to 3mg/kg/day as soon as clinically indicated.Doses should never exceed 5mg/kg/day unless serum levels are monitored. Treatment should be continued for 7-10 days.


Systemic infections:

  • 0-7 days old: 5mg/kg/day initially, dividing dose at 12 hour intervals.
  • 1 week to 1 year old: 6mg/kg/day initially, dividing dose at 12 hour intervals.
  • 1 year to 12 years old: 4.5mg/kg/day, dividing dose at 8 hour intervals.Uncomplicated urinary tract infection:
  • 3mg/kg/day, dividing dose at 8-12 hour intervals.Life threatening infections:
  • 0-7 days old: 5mg/kg/day initially, dividing dose at 12 hour intervals.
  • 1 week to 1 year old: 7.5mg/kg/day initially, dividing dose at 8 hour intervals.
  • 1 year to 12 years old: 6mg/kg/day, dividing dose at 8 hour intervals.

Patients with impaired renal function

  • First dose should be as normal.
  • Subsequent doses should be given less often, with interval depending on degree of renal impairment.
  • Creatinine clearance >70ml/min: 8 hours.
  • Creatinine clearance 35-70ml/min: 12 hours.
  • 24-34ml/min: 18 hours.
  • 16-23ml/min: 24 hours.
  • 10-15ml/min: 36hours.
  • 5-9ml/min: 48 hours.

IV administration

Dilute prescribed dose of Gentamicin in 100 to 200ml of sterile normal saline or glucose 5% in water. Infuse over a period of 30 minutes to 2 hours.

Concentration monitoring

Peak concentration should be measured one hour after IM administration and 30 minutes after a 30-minute infusion has been completed. Trough concentrations should be measured just prior to the next dose.




Common side effects

Gentamicin is a powerful drug with many side effects. Some of these include:


Uncommon side effects


Posted On: 22 July, 2003
Modified On: 4 July, 2006


Created by: myVMC