1 vial

65 cents

  1. Treatment of infections caused by susceptible organisms

  2. Antibiotic synergism for infections caused by Pseudomonas, Acinetobacter and Enterobacteriaceae

80mg in 2ml solution
Add required dose to 100ml of compatible IV fluid and administer over 30 minutes
Dilutions in compatible IV fluid should be prepared immediately before use and any solution not used within 24 hours should be discarded
Store at room temperature

Not recommended by this route in ICU


7mg/kg once daily (round dose up to nearest 40mg)
Monitor levels & see below for repeat dosing


5-7mg/kg daily

Dose in renal impairment [GFR (ml/min)]
<10 2 mg/kg 48 hourly and measure levels
10-20 3 mg/kg 48 hourly and measure levels
>20-30 4 mg/kg 48 hourly and measure levels
2.5 mg/kg 24 hourly and measure levels
3.5 mg/kg 24 hourly and measure levels
4 mg/kg 24 hourly and measure levels

Dose in renal replacement therapy
CAPD 2 mg/kg 48 hourly and measure levels
HD 2 mg/kg post dialysis and measure levels
CVVHDF 4 mg/kg 48 hourly and measure levels

In vitro tests have demonstrated that gentamicin is a bactericidal antibiotic which acts by inhibiting normal protein synthesis in susceptible microorganisms.

It is active against a wide variety of pathogenic bacteria including Escherichia coli, Proteus species (indole-positive and indole-negative), Pseudomonas aeruginosa, species of the Klebsiella-Enterobacter-Serratia group, Citrobacter species, and Staphylococcus species (including penicillin- and methicillin-resistant strains). Gentamicin is also active in vitro against species of Salmonella and Shigella.

The following bacteria are usually resistant to aminoglycosides: Streptococcus pneumoniae, most species of streptococci, particularly group D and anaerobic organisms, such as Bacteroides species or Clostridium species.


  1. Hypersensitivity to gentamicin or other aminoglycosides

As with other aminoglycosides, gentamicin is potentially nephrotoxic. The risk of nephrotoxicity is greater in patients with impaired renal function and in those who receive high dosage or 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; however, it may occur in the absence of these risk factors. Aminoglycoside-induced ototoxicity is usually irreversible.

Gentamicin sulphate contains sodium bisulphite, a sulphite that may cause allergic-type reactions including anaphylactic symptoms and life-threatening or less severe asthmatic episodes in certain susceptible people.
Aminoglycosides should be used with caution in patients with neuromuscular disorders, such as myasthenia gravis, since these drugs may aggravate muscle weakness because of their potential curare-like effects on the neuromuscular junction.

Laboratory Tests
Monitor gentamicin levels:
Collect trough specimens in a SST (Yellow) or Plain (Red) Tube.
For Paediatric and Neonatal patients use a 0.4 mL green microtainer

Trough Level Interpretation:
  • Take a trough level 2-4 hours before the second dose is due

  • If the level is ≤ 0.3mg/L continue on the same dose every 24 hours

  • If the level is >0.3mg/L withhold the next dose & repeat the level after 12 hours

  • If the second level is ≤ 0.3mg/L continue on the same dose every 36 hours

  • If the second level is >0.3mg/L contact the ID registrar or ICU SMO for advice

Drug/Laboratory Test Interactions
None reported

Concurrent and/or sequential use of other potentially neurotoxic and/or nephrotoxic drugs, such as cisplatin, amikacin, neomycin, polymyxin B, colistin, and vancomycin, should be avoided.

The concurrent use of gentamicin with potent diuretics, such as frusemide, 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.

Body as a Whole:
lethargy, urticaria, generalised burning, anaphylactoid reactions
Nervous System:
Ototoxicity, headache, confusion, visual disturbances
Renal System:
Renal failure
Respiratory System:
Respiratory depression, laryngeal oedema
Cardiovascular System:
Hypotension and hypertension
Gastrointestinal System:
Decreased appetite, nausea, vomiting, increased salivation, hepatitis, cholestasis and stomatitis
Haematological System:
Anaemia, leukopaenia, granulocytopaenia, transient agranulocytosis, eosinophilia, increased and decreased reticulocyte counts, and thrombocytopaenia.