Spectrum: Local Antimicrobial Stewardship, for Billings Clinic

Tobramycin

Restricted
Restricted

C. diff Risk

Low

Oral Bioavailability

NA

Approximate Cost

$10-12/day

Spectrum Of Activity

General Spectrum of Activity

Spectrum Of Activity

General Spectrum of Activity

Antibiogram Data

Dosing

Renal

CrCl < 30- See pharmacy policy

  • 3 mg/kg q24-48 hours

  • Goal peak: 8-10 with goal trough <1 (maybe 2 for ICU patient)

Pediatric

Adult

General Information

Common Usage

Common Usage

Pseudomonal and other resistant gram negative infections.

Inhaled form used in cystic fibrosis.

Drug Monitoring

Drug Monitoring

Monitor creatinine at least 2-3 times/week. Discontinue if any signs of ototoxicity.

Extended interval dosing:

  • Normal renal function: check 8-10 hour level and use Hartford nomogram to determine dosing interval

  • CrCl <30: target Trough <1 ug/mL; target peak is 8-10 ug/mL

In critically ill patients, check peak level after the 1st dose to ensure peak target is obtained and renal function may change rapidly.

First Line Indications

First Line Indications

Cystic Fibrosis exacerbation

Adverse Effects

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

Major Interactions

Increased nephrotoxicity

  •  Amphotericin B

  •  Cyclosporine

  •  Cisplatin

  •  NSAIDS

  •  Contrast dye

  •  Vancomycin

Increased ototoxicity

  •  Furosemide

Neuromuscular blockade agents - Respiratory paralysis. Generally do not give IV push.

Additional Information

Additional Information

Restricted to Infectious Diseases and Pulmonary services (Cystic Fibrosis)

Ototoxicity may include both cochlear or vestibular toxicity

Formal audiology assessment if planning to use aminoglycoside for >7d or if symptoms develop. (annual for CF patients who receive IV, q5 years for nebulized tobramycin CF patients)

Inform patient of risk of ototoxicity and to report any symptoms

Pharmacology

Pharmacology

Antimicrobial class: Aminoglycoside

Pregnancy category: D

Average serum half life: 3 hours

Urine penetration: Therapeutic

Lung penetration: Therapeutic

CSF penetration: Poor

Biliary penetration: Moderate

Route of Elimination: Renal