Adult

Metronidazole

Warning

General Information

Nitroimidazole antibiotic

Tablets, injection and suppositories are Formulary antimicrobials: Use in accordance with Trust guidelines

Liquid is a Restricted formulary antimicrobial: For details see OUH netFormulary

AWaRe antibiotic classification: 'Access'. Use as per guidelines.

For all information regarding interactions, contraception, pregnancy and breastfeeding and additional information, see BNF and Summary of Product Characteristics (SPC).

Standard dose

 

Oral dose

Intravenous dose*

Standard dose

400mg TDS

500mg TDS

* Only to be given via the IV route if nil-by-mouth or not absorbing.

Obesity

No dose adjustment required.

Renal and hepatic impairment

Renal impairment

  • No dose adjustment required.
  • HD/HDF/High Flux: Dialysed; give after dialysis.
  • PD: Not dialysed.

 

Hepatic impairment:

  • Mild impairment (Child-Pugh Class A) and Moderate impairment (Child-Pugh Class B): No dose adjustment required.
  • Severe impairment (Child-Pugh Class C) and/or hepatic encephalopathy: The dose of metronidazole should be reduced. Discuss with pharmacy

References

  1. Auribindo Pharma – Milpharm Ltd. Metronidazole 400mg tablets summary of product characteristics. Electronic medicines compendium. Last revision of the text 17/4/25. Accessed via www.medicines.org.uk Accessed 26/3/26.
  2. Baxter Healthcare Ltd. Metronidazole 500mg/100ml Intravenous Infusion summary of product characteristics. Electronic medicines compendium. Last revision of the text 13/12/23. Accessed via www.medicines.org.uk Accessed 26/3/26.
  3. British National Formulary. Metronidazole. BNF online accessed via www.medicinescomplete.com  Accessed 26/3/26.
  4. The Renal Drug Database. Metronidazole. Last updated 13/11/24. Accessed via https://renaldrugdatabase.com Accessed 26/3/26.
  5. Sanford guide [online]. Metronidazole. Last updated 23/3/26. Accessed via https://webedition.sanfordguide.com Accessed 26/3/26.

Editorial Information

Last reviewed: 26 Mar 2026

Next review date: 23 Mar 2029

Author(s): AMST.