Ampicillin for bacterial infection

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Ampicillin for infection

This leaflet is about the use of ampicillin for bacterial infection in children.

Information-Standard-logoThis leaflet has been written for parents and carers about how to use this medicine in children. Our information sometimes differs from that provided by the manufacturers, because their information is usually aimed at adult patients. Please read this leaflet carefully. Keep it somewhere safe so that you can read it again. 

Name of drug

Brand name: Penbritin®, Rimacillin®

There is also a form of ampicillin with another medicine flucloxacillin, this is called co-fluampicil. Co-fluampicil is used for infections that are severe or caused by certain types of bacteria. Brands include Flu-Amp®.

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

It is important that your child takes this medicine in the way that your doctor has told you to so that it kills the harmful bacteria and gets rid of the infection.

What is ampicillin available as?

  • Capsules: 250 mg, 500 mg
  • Liquid medicine (suspension): 125 mg or 250 mg in 5 mL; may contain a small amount of sugar

When should I give ampicillin?

Ampicillin is usually given four times a day. This is usually first thing in the morning, at lunchtime, late afternoon and at bedtime. Ideally, these times are at least 4 hours apart (e.g. 8 am, midday, 4 pm, 8pm).

Give the medicine at about the same times 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 ampicillin (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?

This medicine works best when the stomach is empty, so try to give it to your child ½ - 1 hour before they eat. It is OK for your child to have a glass of water, milk or juice after taking ampicillin.

CapsuleCapsules should be swallowed whole with a glass of water, squash or milk (but not juice). Your child should not chew the capsule.

Liquid-medicineLiquid medicine: Shake the medicine well. Measure out the right amount using a medicine spoon or oral syringe. 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? 

The medicine will start working straight away and your child should start to get better after taking the medicine for 2 days. It is important that they take the whole course of 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 ampicillin, give them the same dose again.
  • If your child is sick more than 30 minutes after having a dose of ampicillin, you do not need to give them another dose. Wait until the next normal dose.

If your child is sick again, seek advice from your GP, pharmacist or hospital. They will decide what to do based on your child’s condition and the specific medicine involved.

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? 

Ampicillin is generally a safe drug, and is unlikely to cause harm if your child has an extra dose by mistake. 

If you worried you may have given your child too much, contact your doctor or local NHS services (111 in England and Scotland, 0845 4647 in Wales). Have the medicine packet 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 that you must do something about

If your child is short of breath or wheezing, or their face, lips or tongue start to swell, or they develop a rash, they may be allergic to ampicillin. Take your child to hospital or call an ambulance straight away. 

If your child gets a lumpy red rash, they may have another infection such as glandular fever. Take them to your doctor.

Other side-effects you need to know about
  • Your child may get some stomach pains, diarrhoea (runny poo), vomiting or feel sick when they first start taking ampicillin. These side-effects are usually mild and improve with time. Giving the medicine just before some food may help. The section 'Important things to know about taking antibiotics' below contains advice on what to do about diarrhoea.
  • If your child has diarrhoea that lasts for longer than 4 days, or it has blood in it, contact your doctor.
  • You may see white patches inside your child’s mouth and throat, and girls may get itching or soreness around the vagina. This is caused by a fungal infection called thrush. If you think your child may have thrush, contact your doctor or pharmacist for advice.

There may, sometimes, be other side-effects that are not listed above. If you notice anything unusual and are concerned, contact your doctor. You can report any suspected side-effects to a UK safety scheme at http://www.mhra.gov.uk/yellowcard.

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 of the medicine has been taken. If you stop giving the antibiotic too soon, the 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 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.
  • 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.

  • Antibiotics only kill bacteria; they do not kill viruses. This means that they do not work against colds, sore throats, flu or other infections that are caused by viruses. Your doctor will not prescribe antibiotics for these illnesses.

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

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • 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 ampicillin?

  • Your child should not have ampicillin if they are allergic to penicillin antibiotics.
  • If your child has ever had an allergic reaction or other reaction to any medicine, tell your doctor. If you have forgotten to tell your doctor, check with the doctor or pharmacist before giving ampicillin to your child.

Where should I keep this medicine? 

  • Keep the medicine 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 it.
  • Keep the medicine in the container it came in.

Who to contact for more information 

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

You can also get useful information from: 
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