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URL of this page: https://medlineplus.gov/druginfo/meds/a682550.html

Ethambutol

pronounced as (e tham' byoo tole)

Why is this medication prescribed?

Ethambutol eliminates certain bacteria that cause tuberculosis (TB). It is used with other medicines to treat tuberculosis and to prevent you from giving the infection to others.

This medication is sometimes prescribed for other uses; ask your doctor or pharmacist for more information.

How should this medicine be used?

Ethambutol comes as a tablet to take by mouth. It usually is taken once a day in the morning. Follow the directions on your prescription label carefully, and ask your doctor or pharmacist to explain any part you do not understand. Take ethambutol exactly as directed. Do not take more or less of it or take it more often than prescribed by your doctor.

What special precautions should I follow?

Before taking ethambutol,

  • tell your doctor and pharmacist if you are allergic to ethambutol or any other drugs.
  • tell your doctor and pharmacist what prescription and nonprescription medications you are taking, especially antacids and vitamins. Antacids interfere with ethambutol, making it less effective. Take ethambutol 1 hour before or 2 hours after antacids.
  • tell your doctor if you have or have ever had kidney disease, gout, or eye disorders such as cataracts.
  • tell your doctor if you are pregnant, plan to become pregnant, or are breast-feeding. If you become pregnant while taking ethambutol, call your doctor.

What special dietary instructions should I follow?

Ethambutol may cause upset stomach. Take ethambutol with food.

What should I do if I forget a dose?

Take the missed dose as soon as you remember it. However, if it is almost time for the next dose, skip the missed dose and continue your regular dosing schedule. Do not take a double dose to make up for a missed one.

What side effects can this medication cause?

Ethambutol may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

  • loss of appetite
  • upset stomach
  • vomiting
  • numbness and tingling in the hands or feet

If you experience any of the following symptoms, call your doctor immediately:

  • blurred vision
  • inability to see the colors red and green
  • sudden changes in vision
  • skin rash
  • itching

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration's (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

What should I know about storage and disposal of this medication?

Keep this medication in the container it came in, tightly closed, and out of reach of children. Store it at room temperature and away from excess heat and moisture (not in the bathroom).

Unneeded medications should be disposed of in special ways to ensure that pets, children, and other people cannot consume them. However, you should not flush this medication down the toilet. Instead, the best way to dispose of your medication is through a medicine take-back program. Talk to your pharmacist or contact your local garbage/recycling department to learn about take-back programs in your community. See the FDA's Safe Disposal of Medicines website (http://goo.gl/c4Rm4p) for more information if you do not have access to a take-back program.

It is important to keep all medication out of sight and reach of children as many containers (such as weekly pill minders and those for eye drops, creams, patches, and inhalers) are not child-resistant and young children can open them easily. To protect young children from poisoning, always lock safety caps and immediately place the medication in a safe location – one that is up and away and out of their sight and reach. http://www.upandaway.org

In case of emergency/overdose

In case of overdose, call the poison control helpline at 1-800-222-1222. Information is also available online at https://www.poisonhelp.org/help. If the victim has collapsed, had a seizure, has trouble breathing, or can't be awakened, immediately call emergency services at 911.

What other information should I know?

Keep all appointments with your doctor and the laboratory. Your doctor will want to check your response to ethambutol. Blood, kidney, and liver tests may be done also. While you are taking ethambutol, your doctor will want to examine your eyes at least every 3-6 months.

Do not let anyone else take your medication. Ask your pharmacist any questions you have about refilling your prescription.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.

Brand names

  • Myambutol®
Last Revised - 08/15/2017