ethambutol
Ethambutol, also known by its brand name Myambutol, is an antibiotic that's used to treat tuberculosis (TB) for people over 13 years old. It's taken with other TB antibiotics as part of a first-choice treatment plan. Ethambutol (Myambutol) works by stopping TB bacteria from growing and surviving. Your dose is based on your body weight. In general, this antibiotic is taken by mouth once a day. Ethambutol (Myambutol) can cause vision problems as a side effect. You'll need to get your eyes checked periodically while you're taking this medication.
What is Ethambutol (Myambutol)?
What is Ethambutol (Myambutol) used for?
How Ethambutol (Myambutol) works
Ethambutol (Myambutol) is an antibiotic. It stops the bacteria that cause TB from making a strong protective covering. This keeps them from growing and surviving.
Drug Facts
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What are the side effects of Ethambutol (Myambutol)?
Common Side Effects
- Blurry vision
- Nausea or vomiting
- Upset stomach
- Stomach pain
- Fever
- Feeling unwell
- Headache
- Dizziness
Other Side Effects
- Numbness and tingling of the arm or leg
- Confusion
- Hallucinations (seeing or hearing things that aren't there)
- Gout attack
- Low blood cell counts
- Abnormal lung scan
Serious Side Effects
- Vision problems: blurry vision, color blindness, blind spots in your vision
- Liver injury: fatigue, nausea, loss of appetite, yellowing of the skin and eyes, dark urine, pale stool
- Allergic reaction: skin rash, redness, scaling
Source:Â DailyMed
The following side effects have also been reported
Along with its needed effects, a medicine may cause some unwanted effects. Although not all of these side effects may occur, if they do occur they may need medical attention.
Check with your doctor immediately if any of the following side effects occur:
Less common
Chills
pain and swelling of joints, especially big toe, ankle, or knee
tense, hot skin over affected joints
Some side effects may occur that usually do not need medical attention. These side effects may go away during treatment as your body adjusts to the medicine. Also, your health care professional may be able to tell you about ways to prevent or reduce some of these side effects. Check with your health care professional if any of the following side effects continue or are bothersome or if you have any questions about them:
Other side effects not listed may also occur in some patients. If you notice any other effects, check with your healthcare professional.
Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.
Pros and cons of Ethambutol (Myambutol)
Cons
Must take with other TB antibiotics
Risk of vision problems
Not approved for children younger than 13 years old
Pharmacist tips for Ethambutol (Myambutol)
To treat active TB, you'll need to take ethambutol (Myambutol) with other TB antibiotics. These can include rifampin, pyrazinamide, and isoniazid. These antibiotics work together to help get rid of the infection.
It's important not to miss any doses of your TB medications, including ethambutol (Myambutol). If you miss doses, the bacteria can become resistant to the antibiotics, making the infection harder to treat. Talk to your prescriber about ways to help you remember to take your medication. They might set up check-ins with you, either in person or through video chat, to make sure you take your dose each day.
You can take ethambutol (Myambutol) with or without food. If it upsets your stomach, try taking it with food next time to help lessen this side effect.
Ethambutol (Myambutol) can cause vision problems. Call your prescriber or eye specialist right away if you notice changes in your vision. This can include blurry vision, blind spots, or trouble telling colors apart.
Make sure to go to your eye exams on time while you're taking ethambutol (Myambutol). Since this medication can affect your vision, your eye specialist needs to periodically check that your eyes are okay.
Frequently asked questions about Ethambutol (Myambutol)
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What are the risks and warnings for Ethambutol (Myambutol)?
Ethambutol (Myambutol) can cause some serious health issues. This risk may be even higher for certain groups. If this worries you, talk to your doctor or pharmacist about other options.
Vision problems
Risk factors: History of vision problems
Ethambutol (Myambutol) can affect your vision. It can cause swelling in the optic nerve (an important part of the eye for vision). This condition is called optic neuritis.
Side effects can include blurry vision, color blindness, and blind spots. Changes in vision can happen in one eye or both. Vision usually gets better over weeks to months after you stop the medication. But in rare cases, vision problems can be permanent.
Ethambutol (Myambutol) isn't recommended for people who already have eye problems. This includes people with cataracts, eye inflammation, optic neuritis, or vision problems from diabetes.
You'll need regular eye exams to check your vision while taking ethambutol (Myambutol). Let your prescriber or eye specialist know right away if you have blurry vision, more blind spots, or trouble telling colors apart.
Liver injury
Some people who've taken ethambutol (Myambutol) have had liver problems. In some cases, they were life-threatening. Before you start treatment, you'll need lab work done to check your liver health. Then, you'll also need regular blood tests while you're taking the medication.
Tell your prescriber right away if you have a fever, loss of appetite, nausea, vomiting, dark urine, or yellowing of your eyes or skin. This could be signs of liver damage.
Ethambutol (Myambutol) dosage forms
Interactions between Ethambutol (Myambutol) and other drugs
Using this medicine with any of the following medicines may cause an increased risk of certain side effects, but using both drugs may be the best treatment for you. If both medicines are prescribed together, your doctor may change the dose or how often you use one or both of the medicines.
- Aluminum Distearate
- Aluminum Hydroxide
- Dihydroxyaluminum Aminoacetate
- Dihydroxyaluminum Sodium Carbonate
- Magaldrate
How much does Ethambutol (Myambutol) cost?
Ethambutol (Myambutol) contraindications
Known inflammation of the optic nerve (optic neuritis)
Can't spot the signs and tell someone about any vision problems or other changes in vision
What are alternatives to Ethambutol (Myambutol)?
Tuberculosis (TB)
Meningococcal carriers (when there's bacteria living in the nose and/or throat, but not causing infection)
Ethambutol (Myambutol) images
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References
Best studies we foundAmerican Lung Association. (n.d.). MAC lung disease.
Centers for Disease Control and Prevention. (2024). Clinical overview of nontuberculous mycobacteria (NTM).
Centers for Disease Control and Prevention. (2025). Treatment for TB disease.
Centers for Disease Control and Prevention. (n.d.). TB 101 for health care workers.
Daley, C. L., et al. (2020). Treatment of nontuberculous mycobacterial pulmonary disease: An official ATS/ERS/ESCMID/IDSA Clinical Practice Guideline. Clinical Infectious Diseases.
Lee, N., et al. (2024). Ethambutol. StatPearls.
Lupin Pharmaceuticals, Inc. (2025). Ethambutol hydrochloride tablet [package insert]. DailyMed.
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