Adult

Metronidazole

Warning

General Information

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.

 

Renal and hepatic impairment

Renal impairment

  • No dose adjustment necessary. 
  • HD/HDF/High Flux -  Dialysed; give after dialysis.
  • PD - Dose as in normal renal function. Not dialysed.

 

Hepatic impairment:

  • The dose of metronidazole should be reduced in severe hepatic impairment.
  • Use with caution in hepatic encephalopathy.

Pregnancy and breastfeeding

Pregnancy

  • Standard doses and short courses are safe to use in pregnancy.
  • High doses or prolonged courses – Avoid (use only in life-threatening infection)

Breastfeeding

  • Significant amount in milk; manufacturer advises avoid large single doses though otherwise compatible; may give milk a bitter taste

Additional information

  • Only give via IV route if nil-by-mouth or not absorbing.
  • Use standard dosing in obese patients.

References

  1. Summary of Product Characteristics (SPC) for Metronidazole. Accessed via www.medicines.org.uk 26/03/18. Last updated 11/04/17
  2. The Renal Drug Database. Metronidazole. Accessed via renaldrugdatabase.com 26/03/18. Last updated 13/11/17
  3. BNF online accessed via www.medicinescomplete.com 4/1/19; last updated 11/12/18

Editorial Information

Next review date: 02 Mar 2026