Spectrum: Local Antimicrobial Stewardship, for Billings Clinic

Metronidazole

C. diff Risk

Low

Oral Bioavailability

Excellent

Approximate Cost

PO: <$1/day
IV: $2-3/day

Spectrum Of Activity

General Spectrum of Activity

Spectrum Of Activity

Dosing

Pediatric

30-40 mg/kg/day divided q8h

Adult

500mg PO/IV q8h

Hepatic

Consider dose reduction with severe hepatic impairment (Child-Pugh C)

General Information

Common Usage

Common Usage

Suspected or confirmed anaerobic infections including:

  •  Intra-abdominal

  •  Biliary

  •  Central nervous system

  •  Clostridium difficile - severe infection IV metronidazole + oral vancomycin.

  •  Giardia

  •  Pelvic infections

Also used in:

  •  Crohns disease

  •  Bacterial vaginosis

  •  Hepatic encephalopathy

Drug Monitoring

Drug Monitoring

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

Adverse Effects

Adverse Effects

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

Major Interactions

Major Interactions

Ethanol - Disulfiram-like reaction

Increases levels of:

  •  Cyclosporine

  •  Lithium

  •  Warfarin

  •  Phenobarbital

  •  Phenytoin

Additional Information

Additional Information

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

Per IDSA guidelines, no longer recommended as first line treatment for C. difficile associated diarrhea. Oral vancomycin preferred.

Pharmacology

Pharmacology

Antimicrobial class: Nitroimidazole

Average serum half life: 8-10 hours

Biliary penetration: Therapeutic

CSF penetration: Therapeutic

Lung penetration: Therapeutic