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.
- 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.
- If you are allergic to this drug; any part of this drug; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you are taking any of these drugs: Efavirenz or rifampin.
- If you are taking any drugs that can raise the chance of liver problems. There are many drugs that can do this. Ask your doctor or pharmacist if you are not sure.
This is not a list of all drugs or health problems that interact with this drug.
Tell your doctor and pharmacist about all of your drugs (prescription or OTC, natural products, vitamins) and health problems. You must check to make sure that it is safe for you to take this drug with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
- Tell all of your health care providers that you take this drug. This includes your doctors, nurses, pharmacists, and dentists.
- Have your blood work checked and an ECG (to see how your heart beats) as you have been told by your doctor.
- Avoid drinking alcohol while taking this drug.
- Low blood cell counts have happened with this drug. If blood cell counts get very low, this can lead to bleeding problems, infections, or anemia. Anemia can be life-threatening. If you have questions, talk with the doctor.
- This drug caused fertility problems in animals. It is not known if it will cause fertility problems in humans. Talk with the doctor.
- Tell your doctor if you are pregnant, plan on getting pregnant, or are breast-feeding. You will need to talk about the benefits and risks to you and the baby.
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 doctor or get medical help right away if you have 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.
- Signs of too much lactic acid in the blood (lactic acidosis) like fast breathing, fast heartbeat, a heartbeat that does not feel normal, very bad upset stomach or throwing up, feeling very sleepy, shortness of breath, feeling very tired or weak, very bad dizziness, feeling cold, or muscle pain or cramps.
- Signs of high blood pressure like very bad headache or dizziness, passing out, or change in eyesight.
- Signs of low blood sugar like dizziness, headache, feeling sleepy, feeling weak, shaking, a fast heartbeat, confusion, hunger, or sweating.
- Change in eyesight.
- A burning, numbness, or tingling feeling that is not normal.
- Change in balance.
- Coughing up blood.
- Chest pain.
- Fever, chills, or sore throat; any unexplained bruising or bleeding; or feeling very tired or weak.
- A type of abnormal heartbeat (prolonged QT interval) can happen with this drug. Call your doctor right away if you have a fast heartbeat, a heartbeat that does not feel normal, or if you pass out.
All drugs may cause side effects. However, many people have no side effects or only have minor side effects. Call your doctor or get medical help if any of these side effects or any other side effects bother you or do not go away:
- Constipation, diarrhea, stomach pain, upset stomach, throwing up, or decreased appetite.
- Pimples (acne).
- Weight loss.
- Dry skin.
- Trouble sleeping.
- Back, bone, joint, or muscle pain.
These are not all of the side effects that may occur. If you have questions about side effects, call your doctor. Call your doctor for medical advice about side effects.
You may report side effects to your national health agency.
Use this drug as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take this drug with food.
- Swallow whole with a drink of water.
- Keep taking this drug as you have been told by your doctor or other health care provider, even if you feel well.
- It is important that you do not miss or skip a dose of this drug during treatment.
- Take a missed dose as soon as you think about it, with food.
- If it is close to the time for your next dose, skip the missed dose and go back to your normal time.
- Do not take 2 doses at the same time or extra doses.
- If you are not sure what to do if you miss a dose, call your doctor.
- Store tablets in the original container at room temperature. Keep the cap tightly closed.
- Store in a dry place. Do not store in a bathroom.
- 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.
- If your symptoms or health problems do not get better or if they become worse, call your doctor.
- Do not share your drugs with others and do not take anyone else’s drugs.
- Some drugs may have another patient information leaflet. If you have any questions about this drug, please talk with your doctor, nurse, pharmacist, or other health care provider.
- This drug comes with an extra patient fact sheet called a Medication Guide. Read it with care. Read it again each time this drug is refilled. If you have any questions about this drug, please talk with the doctor, 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.
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