Experiences with

Metronidazole

Metronidazole is an antibiotic.

It's used to treat skin infections, rosacea and mouth infections, including infected gums and dental abscesses. It's also used to treat conditions such as bacterial vaginosis and pelvic inflammatory disease.

It's also used for infected insect bites, skin ulcers, bed sores and wounds, and to treat and prevent bacterial and parasitic infections.

Metronidazole is only available on prescription.

It comes as tablets, gel, vaginal gel, cream, a liquid you drink or a suppository which is a medicine that you push gently into your anus (bottom). It's also given by injection, but this is usually only done in hospital.

Who can take metronidazole

Most adults and children can take metronidazole.

Who may not be able to take metronidazole

Metronidazole is not suitable for some people. To make sure the tablets, liquid or suppositories are safe for you, tell your doctor if you:

• have ever had an allergic reaction to metronidazole or any other medicine
• are pregnant or breastfeeding
• have liver problems
• are having dialysis
• feel you will not be able to stop drinking alcohol while using metronidazole

To make sure the cream or gel for use on skin is safe for you, tell your doctor if you:

• have ever had an allergic reaction to metronidazole or any other medicines, including any creams or ointments
• are pregnant or breastfeeding

To make sure the vaginal gel is safe for you, tell your doctor if you:

• have ever had an allergic reaction to metronidazole or any other medicine
• are pregnant or breastfeeding
• have liver problems
• feel you will not be able to stop drinking alcohol while using metronidazole
• think you may have vaginal thrush
• are due your period while on treatment

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.

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 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.

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, 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.

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, 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.

Common side effects of tablets, liquid, suppositories or vaginal gel

Keep taking the medicine, but talk to your doctor or pharmacist if these side effects of metronidazole bother you or do not go away. There are things you can do to help cope with them:

Serious side effects are rare and happen in less than 1 in 1,000 people.

Call a doctor or call 111 straight away if:

• the whites of your eyes turn yellow, or your skin turns yellow although this may be less obvious on brown or black skin – these can be signs of liver or gallbladder problems
• you get unexpected infections, mouth ulcers, bruising, bleeding gums, or extreme tiredness – these can be caused by a blood problem
• you have bad stomach pains which may reach through to your back – this can be a sign of pancreatitis
• you have blurred vision or double vision

• you have a stiff neck
• you have a dislike of bright lights
• you're seeing or hearing things that are not there (hallucinating)
• you're feeling confused or having difficulty speaking

You may also have a temperature.

These can be signs of meningitis or signs that metronidazole is affecting your brain.

In rare cases, it's possible to have a serious allergic reaction (anaphylaxis) to metronidazole.

These are not all the side effects of metronidazole tablets, liquid, cream, gel, suppositories or vaginal gel. For a full list see the leaflet inside your medicines packet.

Metronidazole and pregnancy

You can use metronidazole while you're pregnant.

Metronidazole and breastfeeding

It's OK to take metronidazole while you're breastfeeding.

When metronidazole is taken by mouth, as suppositories, or injected, it passes into breast milk in fairly small amounts. It's unlikely to cause side effects in your baby, but a few babies have had diarrhoea.

Metronidazole might make your milk taste metallic, but if this happens it will not harm your baby.

It's best to take metronidazole only for a short time. If you need to take it for longer than a few weeks, talk to your doctor or pharmacist.

When metronidazole is used on your skin, or as a vaginal gel, it is not likely to get into your breast milk, and you can use it for longer than a few weeks if you need to.

When using the cream or gel, be careful that your baby does not come into contact with the areas of your body you have put it on. When using the cream, gel or vaginal gel, wash your hands after you have applied it and before picking up your baby.

If your baby is not feeding as well as usual, has a stomach upset, or has oral thrush (a fungal infection in their mouth), or if you have any other concerns about your baby, talk to your doctor, pharmacist, health visitor or midwife.

Metronidazole and fertility

There's no clear evidence to suggest that taking metronidazole reduces fertility in either men or women. However, speak to a pharmacist or doctor before taking it if you're trying to get pregnant.

Cautions with other medicines

Metronidazole may not mix well with some other medicines. This is not usually a problem when metronidazole is applied to the skin as a gel or cream, but it can be a problem with metronidazole tablets, suppositories, liquid or vaginal gel.

Tell your doctor before you start taking or using metronidazole if you're taking any of these medicines:

• warfarin, a medicine that helps to treat and prevent blood clots
• lithium, used to treat some types of mental health conditions
• disulfiram, used to help people stay off alcohol
• phenytoin or phenobarbitone, used to treat epilepsy
• ciclosporin, used to reduce the activity of the immune system
• fluorouracil or busulfan, used to treat some types of cancer
• any medicines that you take as a liquid, in case these contain alcohol

Mixing metronidazole with herbal remedies and supplements

There are no known problems with taking herbal remedies and supplements alongside metronidazole. However, some remedies and supplements that come as liquids that you drink may also contain alcohol. Check the list of ingredients or ask the supplier or manufacturer.

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