• Basic Info
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What is ethambutol?
Ethambutol is an antibiotic. It prevents growth of the tuberculous bacteria in the body. Ethambutol is used to treat tuberculosis (TB). Ethambutol may also be used for purposes other than those listed in this medication guide.

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What are the possible side effects of ethambutol?

If you experience any of the following serious side effects, stop taking ethambutol and seek emergency medical attention or contact your doctor immediately:

• an allergic reaction (difficulty breathing; closing of the throat; swelling of the lips, tongue, or face; or hives);

• vision changes (e.g., blurring, red-green color blindness);

• a rash;

• numbness or tingling in your fingers, toes, hands, or feet;

• confusion, disorientation, or hallucinations; or

• fever.

Other, less serious side effects may be more likely to occur. Continue to take ethambutol and talk to your doctor if you experience

• stomach upset, nausea, vomiting, abdominal pain, or decreased appetite;

• headache;

• mild dizziness;

• worsening gout; or

• joint pain.

Side effects other than those listed here may also occur. Talk to your doctor about any side effect that seems unusual or that is especially bothersome.

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How should I take ethambutol?
Take ethambutol exactly as directed by your doctor. If you do not understand these instructions, ask your pharmacist, nurse, or doctor to explain them to you. Take each dose with a full glass (8 ounces) of water. Ethambutol can be taken with or without food. Taking ethambutol with food may decrease stomach upset. Take all of the ethambutol that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated. Ethambutol is usually combined with one or more other tuberculosis medicines.

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What is the most important information I should know about ethambutol?
Take all of the ethambutol that has been prescribed for you even if you begin to feel better. Your symptoms may begin to improve before the infection is completely treated. Call your doctor immediately if you experience changes in vision (e.g., blurring, red-green color blindness) or a rash.

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What happens if I miss a dose?
Take the missed dose as soon as you remember. If it is almost time for the next regularly scheduled dose, skip the missed dose and take the next one as directed. Do not take a double dose of this medication.

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What other drugs will affect ethambutol?
Do not take antacids that contain aluminum within several hours of taking a dose of ethambutol. Aluminum will decrease the amount of ethambutol that is absorbed by the body. If you need an antacid, ask your doctor or pharmacist to recommend one that is aluminum free. Drugs other than those listed here may also interact with ethambutol. Talk to your doctor and pharmacist before taking any prescription or over-the-counter medicines, including vitamins, minerals, and herbal products.

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Can I take this if I am pregnant or trying to get pregnant or if I am breastfeeding?

Ethambutol has been assigned to a pregnancy category B by the FDA. While high-dose animal studies have revealed evidence of teratogenicity, ethambutol has been used during human pregnancy with normal outcomes. There are no controlled data in human pregnancy. Ethambutol should only be given during pregnancy when benefit outweighs risk.

Ethambutol crosses the placenta. In one patient, maternal blood, placental blood and cord blood concentrations were 5.5, 5.0, and 4.1, respectively, immediately following delivery. No adverse effects were reported in the infant who had been exposed since 23 weeks gestation. Bobrowitz and colleagues studied 42 pregnancies which involved ethambutol exposure in addition to other antituberculous agents. The majority of these pregnancies were treated throughout gestation. No consistent pattern was noted in the reported fetal adverse effects, which included supernumerary nipple, small umbilical hernia, mild right tibial torsion, congenital dislocation of hips, left hydrocele, minimal metatarsus adductus, and skin tag on finger. Other reports also have not associated ethambutol with teratogenic effects. The initial therapy of active tuberculosis in pregnant patients recommended by the Centers for Disease Control and Prevention includes ethambutol. Ethambutol is also recommended by the American Thoracic Society in cases of suspected drug-resistant tuberculosis.

Ethambutol is excreted into human milk. Ethambutol is considered compatible with breast-feeding by the American Academy of Pediatrics.

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What does my medication look like?
Ethambutol is available with a prescription under the brand name Myambutol. Other brand or generic formulations may also be available. Ask your pharmacist any questions you have about this medication, especially if it is new to you. Myambutol 100 mg--round, white tablets Myambutol 400 mg--round, white tablets

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What happens if I overdose?
Seek emergency medical attention if an overdose is suspected. Symptoms of an ethambutol overdose are unknown.

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What should I discuss with my healthcare provider before taking ethambutol?
Before taking this medication, tell your doctor if you have ever had an allergic reaction to ethambutol; cataracts, diabetic retinopathy, or optic neuritis; or kidney disease. You may not be able to take ethambutol, or you may require a dosage adjustment or special monitoring during treatment if you have any of the conditions listed above. It is not known whether ethambutol will be harmful to an unborn baby. Do not take this medication without first talking to your doctor if you are pregnant or could become pregnant during treatment.

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Can I stop taking the medication if I feel better?
If you have been diagnosed with a disease for which an antibiotic is needed, you must complete the prescribed course of treatment. Even if you start to feel better, do not skip any doses and remember to take the medication until it is all gone.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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