Metronidazole

C. diff Risk

Low

Oral Bioavailability

Complete (100%)

Approximate Cost

$2.58 (PO)
$10.14 (IV)

Dosing

Standard Dose
500mg IV/PO q12h

Intra-Abdominal, Central Nervous System and Clostridium difficile Infections
500mg PO/IV q8h

General Information

Common Usage

Suspected or confirmed anaerobic infections including:

  •  Intra-abdominal

  •  Biliary

  •  Central nervous system

  •  Clostridium difficile: PO used only if cannot get access to PO vancomycin or fidaxomicin. May be used IV in fulminant cases. See Eastern Health CDAD treatment guidelines.

  •  Giardia

  •  Pelvic infections

Also used in:

  •  Crohns disease

  •  Bacterial vaginosis

  •  Hepatic encephalopathy

Drug Monitoring

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

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

Ethanol - Disulfiram-like reaction

Increases levels of:

  •  Cyclosporine

  •  Lithium

  •  Warfarin

  •  Phenobarbital

  •  Phenytoin

Tablet/Capsule Strengths

OPEN BENEFIT (PO)
No prescribing restrictions

Additional Information

IV Administration
Premixed 500 mg bags; infuse over 30-60 min. Premixed bags are not compatible with pumps used in Community IV program

EH prescribing restrictions
None

Community IV Formulary (Metro Region)
NO

Tablets/capsules may be administered via NG route; No liquid formulation available

Pharmacology

Antimicrobial class: Nitroimidazole

Pregnancy category: B

Average serum half life: 10 hours

Biliary penetration: Therapeutic

CSF penetration: Therapeutic

Lung penetration: Therapeutic

Urine penetration: Poor