Ethambutol is used with other medications to treat tuberculosis (TB). Ethambutol is an antibiotic and works by stopping the growth of bacteria.

This antibiotic treats only bacterial infections. It will not work for viral infections (such as common cold, flu). Using any antibiotic when it is not needed can cause it to not work for future infections.

This section contains uses of this drug that are not listed in the approved professional labeling for the drug but that may be prescribed by your health care professional. Use this drug for a condition that is listed in this section only if it has been so prescribed by your health care professional.

This drug may also be used for a certain serious infection (Mycobacterium avium complex-MAC). It may also be used to reduce the risk of MAC infection from occurring again in people with advanced HIV disease.

Take this medication by mouth with or without food as directed by your doctor, usually once daily. This medication may sometimes be taken twice weekly. Take this medication exactly as directed by your doctor. The dosage is based on your age, weight, medical condition, and response to treatment.

If you also take antacids that contain aluminum, take this medication at least 4 hours before the antacid.

For the best effect, take this antibiotic at evenly spaced times. To help you remember, take this medication at the same time(s) every day.

Continue to take this medication (and other TB medications) until the full prescribed amount is finished, even if symptoms disappear. Stopping the medication too early or skipping doses may result in a return of the infection and cause the infection to be more difficult to treat (resistant).

Tell your doctor if your condition lasts or gets worse.

Headache, loss of appetite, upset stomach, or nausea/vomiting may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

Remember that this medication has been prescribed because your doctor has judged that the benefit to you is greater than the risk of side effects. Many people using this medication do not have serious side effects.

Tell your doctor right away if you have any serious side effects, including:

• vision changes (such as blurred/decreased vision, color blindness)
• symptoms of liver disease (such as nausea/vomiting that doesn't stop, unusual tiredness/weakness, severe stomach/abdominal pain, yellowing eyes/skin, dark urine)
• numbness/tingling of arms/legs
• toe/joint pain
• mental/mood disorders (such as confusion, hallucinations)
• signs of a new infection (such as sore throat that doesn't go away, fever)
• easy bleeding/bruising

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before taking ethambutol, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• eye problems (such as optic neuritis, cataracts, diabetic retinopathy)
• liver disease
• kidney disease
• alcohol use

Ethambutol may cause live bacterial vaccines (such as typhoid vaccine) to not work well. Tell your health care professional that you are using ethambutol before having any immunizations/vaccinations.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Alcohol may increase the risk of liver disease. Avoid alcoholic beverages while using this medication.

During pregnancy, this medication should be used only when clearly needed. Discuss the risks and benefits with your doctor.

This medication passes into breast milk but is unlikely to harm a nursing infant. If you have HIV, breast milk may transmit HIV. Consult your doctor before breastfeeding.

See also How to Use section.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as sputum test, eye/vision exams, kidney/liver function, complete blood count) should be done while you are taking this medication. Keep all medical and lab appointments. Consult your doctor for more details.

It is important to take each dose of this medication as scheduled. If you miss a dose, take it as soon as you remember. If it is near the time of the next dose, skip the missed dose. Take your next dose at the regular time. Do not double the dose to catch up.

Store at room temperature away from light and moisture. Do not store in the bathroom. Keep all medications away from children and pets.

Do not flush medications down the toilet or pour them into a drain unless instructed to do so. Properly discard this product when it is expired or no longer needed. Consult your pharmacist or local waste disposal company.