Antimicrobials
Gentamicin

Gentamicin

Restricted

Low
None
$3 + monitoring

Dosing

General Information

Empiric (in combination) or targeted therapy for suspected or confirmed resistant gram negative infections.

Empiric therapy for pyelonephritis.

Used synergistically in enterococcal or streptococcal endocarditis.

Monitor creatinine at least 3 times/week. Discontinue if any signs of ototoxicity.

Once daily dosing: Hartford nomogram.

Renal dysfunction and extended interval dosing: Peak monitoring poorly supported by literature, but target peak 8-10mcg/mL; trough 1-2mcg/mL

Trough is 30 minutes before next dose. Peak is 30 minutes after 30 minute infusion

In critically ill patients, check peak level after the 1st dose as volume of distribution and renal function may change rapidly.

Nephrotoxicity (non-oliguric)

  •  Avoid concomitant nephrotoxins
  •  Less common with once daily dosing
  •  Greater toxicity with longer duration and supratherapeutic trough levels

Vestibulocochlear toxicity

  • Irreversible
  • Require audiology testing if prolonged use

Can exacerbate neuromuscular blockade

  •  Contraindicated in patients with myasthenia gravis

Increased nephrotoxicity

  •  Amphotericin
  •  Vancomycin
  •  Cyclosporin
  •  NSAIDs
  •  Contrast

Increased ototoxicity

  •  Loop diuretics (e.g. furosemide)

Non-depolarizing muscle relaxants may be potentiated

Restricted to Infectious Diseases, OBGYN (FBC) and NICU

Formal audiology assessment if planning to use aminoglycoside for >7d or if symptoms develop.

Inform patient of risk of ototoxicity and to report any symptoms.

Antimicrobial class: Aminoglycoside

Pregnancy category: D

Average serum half life: 2 hours

Biliary penetration: Moderate

CSF penetration: Poor

Lung penetration: Therapeutic

Urine penetration: Therapeutic