Gentamicin

C. diff Risk

Low

Oral Bioavailability

NA

Approximate Cost

General Information

Common Usage

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

Empiric therapy for pyelonephritis.

Used synergistically in enterococcal endocarditis.

Drug Monitoring

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

Pharmacist will consult, adjust doses and order serum drug levels and renal function monitoring as per MSH Policy.

Adverse Effects

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

Major Interactions

Increased nephrotoxicity

  •  Amphotericin

  •  Vancomycin

  •  Cyclosporin

  •  NSAIDs

  •  Contrast

Increased ototoxicity

  •  Loop diuretics (e.g. furosemide)

Non-depolarizing muscle relaxants may be potentiated

Additional Information

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.

Pharmacology

Antimicrobial class: Aminoglycoside

Pregnancy category: D

Average serum half life: 2 hours

Biliary penetration: Moderate

CSF penetration: Poor

Lung penetration: Therapeutic

Urine penetration: Therapeutic