Ethambutol for the treatment of tuberculosis

This leaflet is about the use of ethambutol for the treatment of tuberculosis (TB for short). Your child will have to take up to four medicines for at least 6 months to cure their TB.

Information Standard quality markThis leaflet has been written specifically 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.

It is essential that your child takes all their medicines daily, as explained by the doctor, and continues until the doctor tells you to stop.

Name of drug

Ethambutol

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

The bacteria that cause TB are hard to kill. Your child will have to take up to four medicines for at least 6 months. Ethambutol is one of these key medicines. It is given for the first two months of a treatment course.

Your child may not necessarily have symptoms from the TB infection. Any symptoms should start to improve soon after starting treatment. You MUST continue to give the medicines until your doctor tells you to stop. If you stop too soon, or your child does not take the medicines as your doctor has told you to, the bacteria may not be killed and the TB may come back. 

It is also possible that the bacteria will become ‘resistant’ to (no longer be killed by) the first drugs, which means that they will no longer work. This may mean that other stronger drugs will have to be used, or the TB will no longer be treatable.

What is ethambutol available as?

  • Tablets: 100 mg (yellow), 400 mg (grey)
  • Liquid medicine can be ordered specially from your pharmacist

When should I give ethambutol?

Ethambutol (along with other TB drugs) is usually given once each day. This can be in the morning or the evening.

Give the medicines at about the same time 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 ethambutol (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?

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


Liquid medicine: Measure out the right amount 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 will start to feel better after taking the TB medicines for about 2 weeks and should have fewer symptoms. They MUST continue to take the drugs every day until the doctor says to stop treatment. This will be for at least 2 months for ethambutol and at least 6 months for the other TB medicines. 

What if my child is sick (vomits)?

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

What if I forget to give it?

Give the missed dose when you remember during the day, as long as this is at least 12 hours before the next dose is due.

What if I give too much? 

If you think you may have given your child too much ethambutol, contact your doctor or NHS Direct (0845 4647). Have the medicine 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 you must do something about

Your child may have problems with their eyesight: they may find it difficult to tell colours apart, have blurry vision, or may not be able to see things clearly at the edge of their vision. If you or your child think that their eyesight is changing, contact your doctor straight away; do not give any more ethambutol. These changes will reverse when the treatment is stopped.

If your child seems to bruise more easily or bleeding doesn’t stop as quickly as you would expect, continue to give ethambutol, but contact your doctor straight away, as there may be a problem with your child’s blood.

  • If your child feels numbness, weakness or ‘pins and needles’ in their arms or legs, continue to give ethambutol but contact your doctor, as there may be a problem with your child’s nerves. 
  • Your child may develop itchiness or a rash. Try applying a moisturising cream or anti-itch cream. If this does not help, continue to give ethambutol, but contact your doctor, in case your child is allergic to ethambutol. 

Other side-effects you need to know about

Your child may get the following side-effects when they first start taking ethambutol. These usually get better after a week, but if they are still a problem after this, contact your doctor.

  • They may get an upset stomach, cramps or diarrhoea.
    It may help to give each dose with some food. 
  • They may lose their appetite (feel less hungry). Encourage them to eat small meals often.
  • They may develop a metallic taste in their mouth.
    Eating citrus fruits or taking sips of water may help.

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

  • You can give your child medicines that contain paracetamol or ibuprofen, unless your doctor has told you not to.
  • Ethambutol should not be taken with some medicines that you get on prescription. Tell your doctor about all medicines your child is taking before starting ethambutol.
  • 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?

  • Depending on the age of your child, your doctor may test their eyesight before and during treatment with ethambutol.

Keep all your clinic appointments, as your doctor or nurse needs to check how your child is doing.

General advice about medicines

  • Give medicines at about the same times each day, to help you remember.
  • Only give this medicine to your child. 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.
  • Make sure that you always have enough medicine. Order a new prescription at least 2 weeks before you will run out.
  • Make sure that the medicine you have at home has not reached the ‘best before’ or ‘use by’ date on the packaging. Give old medicines to your pharmacist to dispose of.

Where I should keep this medicine? 

  • Keep the medicine in a cupboard, away from heat and direct sunlight. 
  • 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 child’s doctor, pharmacist or nurse will be able to give you more information about ethambutol and about other medicines used to treat TB.


You can also get useful information from:


Publication Date

12/9/2011

Copyright Disclaimer

Version 1, August 2011. © NPPG, RCPCH and WellChild 2011, all rights reserved. Reviewed by: August 2013. 

The primary source for the information in this leaflet is the British National Formulary for Children. For details on any other sources used for this leaflet, please contact us through our website, www.medicinesforchildren.org.uk.

We take great care to make sure that the information in this leaflet is correct and up-to-date. However, medicines can be used in different ways for different patients. It is important that you ask the advice of your doctor or pharmacist if you are not sure about something. This leaflet is about the use of these medicines in the UK, and may not apply to other countries. The Royal College of Paediatrics and Child Health (RCPCH), the Neonatal and Paediatric Pharmacists Group (NPPG), WellChild and the contributors and editors cannot be held responsible for the accuracy of information, omissions of information, or any actions that may be taken as a consequence of reading this leaflet.