Pediatric Medication

This information from Lexicomp® explains what you need to know about this medication, including what it’s used for, how to take it, its side effects, and when to call your healthcare provider.

Brand Names: US


  • A type of abnormal heartbeat (prolonged QT interval) can happen with this drug. The chance may be raised if you also take other drugs that can cause this type of abnormal heartbeat. Call the doctor right away if your child has a fast or abnormal heartbeat, dizziness, or if your child passes out.
  • Your child will need an ECG before starting this drug and during treatment. Talk with the doctor.

What is this drug used for?

  • It is used to treat TB (tuberculosis).
  • This drug is taken with other drugs. Be sure you know about the warnings, benefits, and risks of these other drugs. Talk with the doctor if you have questions or concerns about any of the drugs.

What do I need to tell the doctor BEFORE my child takes this drug?

  • If your child is allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell the doctor about the allergy and what signs your child had.
  • If your child is taking any drugs that can raise the chance of liver problems. There are many drugs that can do this. Ask the doctor or pharmacist if you are not sure.
  • If your child takes any drugs (prescription or OTC, natural products, vitamins) that must not be taken with this drug, like certain drugs that are used for HIV, infections, seizures, and others. There are many drugs that must not be taken with this drug.

If your child is breast-feeding a baby:

  • If your child is breast-feeding a baby or plans to breast-feed a baby. Be sure your child does not breast-feed a baby while taking this drug and for 27.5 months after the last dose. If infant formula is not available and your child must breast-feed, talk to the doctor about how to watch your child’s baby for signs of side effects like liver problems.

This is not a list of all drugs or health problems that interact with this drug.

Tell the doctor and pharmacist about all of your child’s drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe to give this drug with all of your child’s other drugs and health problems. Do not start, stop, or change the dose of any drug your child takes without checking with the doctor.

What are some things I need to know or do while my child takes this drug?

  • Tell all of your child’s health care providers that your child is taking this drug. This includes your child’s doctors, nurses, pharmacists, and dentists.
  • Have your child’s blood work and other lab tests checked as you have been told by the doctor.
  • Alcohol may interact with this drug. Be sure your child does not drink alcohol.
  • In one study, an increased risk of death was seen in people taking this drug compared to people not taking it. The cause of this is not known. This drug is only for use when other drugs cannot be used.

If your child is pregnant:

  • Tell the doctor if your child is pregnant or becomes pregnant. You will need to talk about the benefits and risks of your child using this drug while pregnant.

What are some side effects that I need to call my child’s doctor about right away?

WARNING/CAUTION: Even though it may be rare, some people may have very bad and sometimes deadly side effects when taking a drug. Tell your child’s doctor or get medical help right away if your child has any of the following signs or symptoms that may be related to a very bad side effect:

  • Signs of an allergic reaction, like rash; hives; itching; red, swollen, blistered, or peeling skin with or without fever; wheezing; tightness in the chest or throat; trouble breathing, swallowing, or talking; unusual hoarseness; or swelling of the mouth, face, lips, tongue, or throat.
  • Signs of liver problems like dark urine, tiredness, decreased appetite, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
  • Chest pain.
  • Coughing up blood.
  • A burning, numbness, or tingling feeling that is not normal.

What are some other side effects of this drug?

All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your child’s doctor or get medical help if any of these side effects or any other side effects bother your child or do not go away:

  • Headache.
  • Muscle or joint pain.
  • Dry skin.
  • Upset stomach or throwing up.
  • Stomach pain.
  • Decreased appetite.
  • Trouble sleeping.

These are not all of the side effects that may occur. If you have questions about side effects, call your child’s doctor. Call your child’s doctor for medical advice about side effects.

You may report side effects to your national health agency.

How is this drug best given?

Give this drug as ordered by your child’s doctor. Read all information given to you. Follow all instructions closely.

All products:

  • Give this drug with food.
  • Keep giving this drug to your child as you have been told by your child’s doctor or other health care provider, even if your child feels well.
  • It is important that your child does not miss or skip a dose of this drug during treatment.

20 mg tablets:

  • The tablets may be split based on the dose that is needed. If splitting the tablets, only split on the score line.
  • If your child cannot swallow tablets, the tablet may be crushed and added to a small amount of soft food like yogurt, apple sauce, mashed banana, or porridge. Give the mixture right away. Do not store for future use. Make sure no drug is left in the container; add more soft food and have your child take it right away.
  • You may also mix the tablets in water in a cup. Use 1 teaspoon (5 mL) of water for up to 5 tablets. If needed, you can add at least 1 more teaspoon of drink or soft food. This includes water, milk products, apple juice, orange juice, cranberry juice, carbonated drinks, yogurt, apple sauce, mashed banana, or porridge. Mix well and give right away. If your child’s dose is more than 5 tablets, do these steps again. Add more drink or soft food to rinse the cup and have your child take right away.
  • Those who have feeding tubes may use this drug. Use as you have been told. Flush the feeding tube after this drug is given.

100 mg tablets:

  • Have your child swallow whole with a drink of water.

What do I do if my child misses a dose?

Weeks 1 and 2:

  • Skip the missed dose and go back to your child’s normal time.

Week 3 or more:

  • Give a missed dose as soon as you think about it and go back to your child’s normal time.
  • Be sure that there are at least 24 hours between giving a missed dose and the next dose. Do not give more doses in a week than you were told by your child’s doctor.
  • If you are not sure what to do if your child misses a dose, call the doctor.

How do I store and/or throw out this drug?

All products:

  • Store at room temperature protected from light. Store in a dry place. Do not store in a bathroom.
  • Store in the original container with the lid tightly closed.
  • Keep all drugs in a safe place. Keep all drugs out of the reach of children and pets.
  • Throw away unused or expired drugs. Do not flush down a toilet or pour down a drain unless you are told to do so. Check with your pharmacist if you have questions about the best way to throw out drugs. There may be drug take-back programs in your area.

20 mg tablets:

  • The bottle has a desiccant in it to keep the drug dry. Keep the desiccant in the bottle. Do not let your child eat or swallow the desiccant.

100 mg tablets:

  • If stored outside of the original container, throw away any part not used after 3 months.

General drug facts

  • If your child’s symptoms or health problems do not get better or if they become worse, call your child’s doctor.
  • Do not share your child’s drug with others and do not give anyone else’s drug to your child.
  • Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your child’s doctor, nurse, pharmacist, or other health care provider.
  • If you think there has been an overdose, call your poison control center or get medical care right away. Be ready to tell or show what was taken, how much, and when it happened.

Consumer Information Use and Disclaimer

This generalized information is a limited summary of diagnosis, treatment, and/or medication information. It is not meant to be comprehensive and should be used as a tool to help the user understand and/or assess potential diagnostic and treatment options. It does NOT include all information about conditions, treatments, medications, side effects, or risks that may apply to a specific patient. It is not intended to be medical advice or a substitute for the medical advice, diagnosis, or treatment of a health care provider based on the health care provider’s examination and assessment of a patient’s specific and unique circumstances. Patients must speak with a health care provider for complete information about their health, medical questions, and treatment options, including any risks or benefits regarding use of medications. This information does not endorse any treatments or medications as safe, effective, or approved for treating a specific patient. UpToDate, Inc. and its affiliates disclaim any warranty or liability relating to this information or the use thereof. The use of this information is governed by the Terms of Use, available at

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Last Updated

Monday, December 12, 2022