Antimicrobials
Metronidazole

Metronidazole

Low
Excellent

Spectrum of Activity

Dosing

General Information

Administration

  • Infuse IV over 30-60 minutes

  • Avoid contact of drug solution with equipment containing aluminum

No preparation, pre-made IV bags

Suspected or confirmed anaerobic infections including:

  • Intra-abdominal

  • Biliary

  • Central nervous system

  • Clostridium difficile

  • Giardia

  • Pelvic infections

Also used in:

  • Crohns disease

  • Bacterial vaginosis

  • Hepatic encephalopathy

Tier 2 Protected Antimicrobial

  • Broad spectrum, but 1st line for common infections, comes with a high risk of poor stewardship if initial workup and follow-up are not in place

Strategies Used:

  1. Appropriate workup initially
  2. Pharmacists audit/de-escalate
  3. Set EBM Duration
  • CBC with differential at baseline, during and after prolonged or repeated courses

  • Assess for peripheral/optic neuropathy with prolonged therapy (>6wks) or if symptoms develop

  • In severe renal impairment, monitor closely for CNS adverse effects (neuropathy, encephalopathy, and seizures)

  • GI symptoms common - Especially nausea/vomiting and metallic taste

  • Peripheral/optic neuropathy with extended therapy

  • Disulfiram-like reaction (severe vomiting)

  • Rare neurotoxicity including aseptic meningitis and encephalopathy

  • Ethanol - Disulfiram-like reaction (avoid concomitant use)

Increases levels of:

  • Cyclosporine

  • Lithium

  • Warfarin (increased INR)

  • Phenobarbital

  • Phenytoin

Antimicrobial class: Nitroimidazole

Pregnancy category: B

Average serum half life: 10 hours

Urine penetration: Poor, ~20% unchanged drug excreted through urine

Lung penetration: Therapeutic

CSF penetration: Therapeutic

Biliary penetration: Therapeutic

Bacterial, protozoal and ameobic DNA is fragmented by reactive nitroso-imidazole radicals.