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How and when to take or use metronidazole

Tablets, liquid or suppositories

Metronidazole tablets, liquid and suppositories are prescribed for a number of types of infections.

Dosage for tablets, liquid or suppositories

The type of metronidazole your doctor prescribes, the dose and how long you need to take it for depends on the type of infection and how serious it is.

Some infections can be treated with a single dose, while others may need a 2-week course. Children's doses are lower and depend on the age or weight of your child.

Follow the instructions from your doctor or pharmacist.

How to take metronidazole tablets

Swallow the tablets whole with a drink of water, after you've eaten some food.

How to take metronidazole liquid

Metronidazole liquid does not need to be taken after food.

This medicine comes with a plastic syringe or spoon to help you measure out the right dose. If you do not have one, ask your pharmacist for one. Do not use a kitchen teaspoon as it will not measure the right amount.

How to use metronidazole suppositories

Your doctor may prescribe metronidazole suppositories if you have difficulty swallowing medicines. You'll usually use them 3 times a day. Follow the instructions that come in the packaging with your medicine.

When to take tablets, liquid or suppositories

If you need to take several doses of metronidazole a day, try to space them evenly. For example, if you take your medicine 3 times a day, this could be first thing in the morning, mid-afternoon, and at bedtime.

How long to take metronidazole tablets, liquid or suppositories for

It's very important to keep taking metronidazole for as long as your doctor has prescribed it.

Important: Finishing your course of tablets, liquid or suppositories

Carry on taking metronidazole tablets, liquid or suppositories until you have finished the course, even if you feel better. If you stop your treatment early, the infection could come back.

If you forget to take metronidazole tablets, liquid or suppositories

If you forget to take a dose of metronidazole tablets, liquid or suppositories, take it as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and take your next dose at the usual time.

Never take 2 doses at the same time. Never take an extra dose to make up for a forgotten one.

If you often forget doses, it may help to set an alarm to remind you. You could also ask your pharmacist for advice on other ways to remember your medicines.

If you take too much metronidazole tablets, liquid or suppositories

Taking an extra dose of metronidazole tablets, liquid or suppositories is unlikely to harm you or your child.

Speak to your pharmacist or doctor if you're worried or you take more than 1 extra dose.

Cream or gel for skin infections

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. Follow the instructions from your doctor or pharmacist.

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.

How to put on metronidazole cream or gel

Put a thin layer of cream or gel onto the area you're treating and rub it in very gently.

Try to avoid getting it into your eyes, as it can sting. If you do get some in your eye, wash it out immediately with cold water.

Remember to wash your hands before and after using it.

How long to use metronidazole cream or gel for

It's very important to keep using metronidazole cream or gel for as long as your doctor has prescribed it.

Important: Finishing your course of cream or gel

Carry on using metronidazole cream or gel until you have finished the course, even if you feel better. If you stop your treatment early, the infection could come back.

If you forget to use metronidazole cream or gel

If you forget to use metronidazole cream or gel, put it on as soon as you remember, unless it's nearly time for your next dose. In this case, just leave out the missed dose and use your next dose at the usual time.

Do not use it more than twice a day unless your doctor tells you to.

If you use too much metronidazole cream or gel

If you put on too much cream or gel, or if you get some in your mouth, it's unlikely to harm you.

Talk to your pharmacist or doctor if you're worried, or if you or your child swallows a lot of it.

Vaginal gel

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

Dosage for metronidazole vaginal gel

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

How to use metronidazole vaginal gel

Follow the instructions that come in the packaging along with your medicine. These will tell you how to fill the applicator with gel and put it into your vagina.

Do not have sex while using the vaginal gel.

It's recommended that you do not use the gel while having your period.

How long to use metronidazole vaginal gel for

It's very important to keep using metronidazole vaginal gel for as long as your doctor has prescribed it.

Important: Finishing your course of vaginal gel

Carry on using metronidazole vaginal gel until you have finished the course, even if you feel better. If you stop your treatment early, the infection could come back.

If you forget to use metronidazole vaginal gel

If you forget to use metronidazole vaginal gel, use it as soon as you remember, unless it's nearly time for your usual dose. In this case, skip the missed dose and use your next dose at the usual time.

Do not use it more than once a night.

If you use too much metronidazole vaginal gel

If you use too much vaginal gel it's unlikely to harm you.

Talk to your pharmacist or doctor if you're worried.

Page last reviewed: 17 November 2021
Next review due: 17 November 2024