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Detailed medicine guidance

How and when to take or use metronidazole

NHS medicines information on dosage for metronidazole, how to take it and what to do if you miss a dose or take too much.

About this information

This NHS content is written for people in England. Medicine names, availability, prescribing and services may differ in other countries.

Dosage and how to take metronidazole

Dosage for tablets, liquid or suppositories

Some infections can be treated with a single dose, while other infections may need a 2-week course. If you're prescribed a 2-week course of tablets, you'll usually take them 2 or 3 times a day.

Children's doses are lower and depend on the age or weight of your child.

Your doctor may prescribe metronidazole suppositories if you have difficulty swallowing medicines. You'll usually use them 3 times a day, although you may be told to use them twice daily if you are going to continue treatment with suppositories for longer than 3 days.

Dosage for cream or gel

If you're prescribed metronidazole cream or gel for rosacea, you'll normally use it twice a day for about 2 months. Treatment can sometimes last longer. It is important to continue using the treatment until your doctor tells you to stop.

If you're using the cream or gel for a skin infection, or infected ulcers or wounds, you'll usually put it on once or twice a day.

Follow your doctor or pharmacist's instructions and continue treatment until your infection has healed.

Dosage for vaginal gel

For treating bacterial vaginosis, you'll use an applicator to put the metronidazole gel into your vagina.

The usual dose for treating bacterial vaginosis is 1 applicator full, every night for 5 nights.

View the original NHS website page ↗. Refreshed 19 August 2026.

Licensed under the Open Government Licence v3.0 ↗. MyPHU is independent and is not endorsed by the NHS.

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