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Metronidazole for bacterial infections

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Metronidazole for bacterial infections

This leaflet is about the use of metronidazole for bacterial infections.

Information-Standard-logoThis leaflet has been written specifically for parents and carers about the use of this medicine in children. The information may differ from that provided by the manufacturer. Please read this leaflet carefully. Keep it somewhere safe so that you can read it again. 

If your child has ever had a reaction to any antibiotic, check with your doctor that your child can have metronidazole, before giving it.

Name of drug

Metronidazole
Brand names:
Flagyl®, Flagyl S®, Norzol®

Why is it important for my child to take this medicine?

It is important that your child takes this medicine so that it kills the harmful bacteria and gets rid of their infection.

What is metronidazole available as?

Tablets: 200 mg, 400 mg
Liquid medicine (suspension): 200 mg in 5 mL

When should I give metronidazole?

Metronidazole is usually given three times a day. This should be in the morning, early afternoon and at bedtime. Ideally, these times are at least 6 hours apart, for example 8 am, 2 pm and 8 pm.

Give the medicine at about the same time(s) each day so that this becomes part of your child’s daily routine, which will help you to remember.

How much should I give?

Your doctor will work out the amount of metronidazole (the dose) that is right for your child. The dose will be shown on the medicine label.

It is important that you follow your doctor’s instructions about how much to give.

How should I give it?

TabletsTablets should be swallowed with a glass of water, milk or juice. Your child should not chew the tablet.

Liquid medicine with oral syringeLiquid medicine: Shake the bottle well and measure out the right amount using an oral syringe or medicine spoon. You can get these from your pharmacist. Do not use a kitchen teaspoon as it will not give the right amount.

When should the medicine start working?

Your child should start to get better after taking the medicine for 2–3 days. It is important that they take the whole course of the medicine that has been prescribed. Do not stop early.

What if my child is sick (vomits)?

  • If your child is sick less than 30 minutes after having a dose of metronidazole, give them the same dose again.
  • If your child is sick more than 30 minutes after having a dose of metronidazole, you do not need to give them another dose. Wait until the next normal dose.

What if I forget to give it?

Do not give the missed dose. Just give the next dose as usual.

What if I give too much?

Metronidazole is normally a safe drug. It is unlikely to cause any problems if you give an extra dose by mistake. If you are worried that you may have given your child too much metronidazole, contact your doctor or local NHS services (111 in England and Scotland; 0845 4647 in Wales). Have the medicine or packaging with you if you telephone for advice.

Are there any possible side-effects?

We use medicines to make our children better, but sometimes they have other effects that we don’t want (side-effects).

Side-effects are rare with metronidazole and do not usually last for long. They will get better after a day or two as your child’s body gets used to the medicine, and should go away when the treatment course is finished.

Side-effects you must do something about

Serious side-effects are very unlikely with metronidazole.

If your child gets bad stomach pain that reaches through to their back, contact your doctor or take your child to hospital straight away as they may have a problem with their pancreas.

  • If your child gets a yellowish tinge to the skin or whites of the eyes, contact your doctor straight away, as there may be a problem with their liver.
  • If your child is very tired, or has unusual bruising or bleeding, contact your doctor as there may be a problem with their blood.
Other side-effects you need to know about
  • Your child may have diarrhoea, stomach pains, feel sick or be sick (vomit) when they first start to take metronidazole. The box overleaf gives advice on what to do.
  • Contact your doctor if your child has diarrhoea that goes on for more than 4 days or if it is severe and watery, or contains blood.
  • Your child’s tongue may feel furry to them. Sucking or chewing a piece of fruit or a sweet may help. Your child may also get mouth ulcers. If this occurs contact your doctor.
  • Your child may have a metallic or bitter taste in their mouth. Eating citrus fruits or taking sips of water may help.
  • Your child may feel less hungry (lose their appetite). Encourage them to eat small meals often.

There may, sometimes, be other side-effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor.

Can other medicines be given at the same time as metronidazole?

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • Metronidazole should not be taken with some medicines that you get on prescription. Tell your doctor and pharmacist about any other medicines your child is taking before giving metronidazole.
  • Check with your doctor or pharmacist before giving any other medicines to your child. This includes herbal or complementary medicines.

Is there anything else I need to know about this medicine?

If your child has ever had a reaction to any antibiotic, tell your doctor or pharmacist before giving metronidazole.

  • Teenagers should be aware that they must not drink alcohol while taking metronidazole, and for 48 hours after finishing the course, as it is likely to make them unwell. They are likely to feel sick (nausea) or be sick (vomit), have stomach pains, hot flushes, headache and a fast or uneven heartbeat.

Important things to know about taking antibiotics

  • It is important that your child completes the course of antibiotic. This means that they must take the medicine for the number of days that the doctor has told you to, or until all the medicine has been taken. If you stop giving the antibiotic too soon, the troublesome bacteria that are left will start to multiply again, and may cause another infection. There is also a risk that these bacteria will be ‘resistant’ to (no longer killed by) the first antibiotic. This means that it might not work next time, and your child might need a different antibiotic, which might not work as well or cause more side-effects.
  • Children are sometimes sick (vomit) or get diarrhoea when taking antibiotics. Encourage them to drink water to replace the fluid they have lost. Please see your doctor if it is severe or your child is drowsy.
  • Do not give your child any medicine to stop the diarrhoea unless your doctor has told you to.
  • Try to give the medicine at about the same times each day, to help you remember, and to make sure that there is the right amount of medicine in your child’s body to kill the bacteria.
  • Only give this medicine to your child for their current infection.
  • Never save medicine for future illnesses. Give old or unused antibiotics to your pharmacist to dispose of.
  • Only give the antibiotic to the child for whom it was prescribed. Never give it to anyone else, even if their condition appears to be the same, as this could do harm.

If you think someone else may have taken the medicine by accident, contact your doctor for advice.

Where I should keep this medicine?

  • Keep the medicines in a cupboard, away from heat and direct sunlight. It does not need to be kept in the fridge.
  • Make sure that children cannot see or reach the medicine.
  • Keep the medicine in the container it came in.

Who to contact for more information

Your doctor, pharmacist or nurse will be able to give you more information about metronidazole and about other medicines used to treat bacterial infections.

You can also get useful information from: 
Publication date: 
04/05/2012

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