Medically reviewed by Drugs.com. Last updated on May 15, 2023.
- This medicine may cause very bad and sometimes deadly liver problems like hepatitis. Call your doctor right away if you have signs of liver problems like dark urine, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- The chance of liver problems is higher the older you are. The chance may also be raised by drinking alcohol every day, long-term liver problems, or injection drug use. The chance of liver problems may also be raised in women, mainly women who are black or Hispanic or who have just had a baby. Most of the time, liver problems caused by Rifamate (rifampin and isoniazid) happen within the first 3 months of care, but they can happen at any time. Most of the time, liver function has gone back to normal but sometimes it has not. Blood work will need to be done before starting this drug and while taking it. If you have questions, talk with the doctor.
- If you have active liver disease, talk with your doctor. This medicine may not be right for you.
Uses of Rifamate:
- It is used to treat TB (tuberculosis).
What do I need to tell my doctor BEFORE I take Rifamate?
- If you are allergic to Rifamate (rifampin and isoniazid); any part of Rifamate (rifampin and isoniazid); or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have any of these health problems: Gout or liver problems.
- If you have had very bad side effects while taking isoniazid in the past, like liver problems, drug fever, chills, or arthritis.
- If you had liver problems while taking some other drug in the past.
- If you take any drugs (prescription or OTC, natural products, vitamins) that must not be taken with Rifamate (rifampin and isoniazid), like certain drugs that are used for HIV, infections, or depression. There are many drugs that must not be taken with Rifamate (rifampin and isoniazid). Your doctor or pharmacist can tell you if you are taking a drug that must not be taken with Rifamate (rifampin and isoniazid).
This is not a list of all drugs or health problems that interact with Rifamate (rifampin and isoniazid).
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 Rifamate (rifampin and isoniazid) with all of your drugs and health problems. Do not start, stop, or change the dose of any drug without checking with your doctor.
What are some things I need to know or do while I take Rifamate?
- Tell all of your health care providers that you take Rifamate (rifampin and isoniazid). This includes your doctors, nurses, pharmacists, and dentists.
- Have an eye exam as you have been told by your doctor.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take Rifamate (rifampin and isoniazid).
- Avoid drinking alcohol while taking Rifamate (rifampin and isoniazid).
- If you have high blood sugar (diabetes), you will need to watch your blood sugar closely. Tell your doctor if you get signs of high blood sugar like confusion, feeling sleepy, more thirst, more hungry, passing urine more often, flushing, fast breathing, or breath that smells like fruit.
- Some foods and drinks, like cheese and red wine, may cause sudden, severe high blood pressure when you are taking Rifamate (rifampin and isoniazid). This effect can be deadly. Talk with your doctor about your risk for this effect. Get a list of foods and drinks to avoid. Avoid these foods and drinks for as long as your doctor has told you after Rifamate (rifampin and isoniazid) is stopped.
- This medicine may stain contact lenses.
- A severe and sometimes deadly reaction has happened. Most of the time, this reaction has signs like fever, rash, or swollen glands with problems in body organs like the liver, kidney, blood, heart, muscles and joints, or lungs. If you have questions, talk with the doctor.
- A very bad skin reaction (Stevens-Johnson syndrome/toxic epidermal necrolysis) may happen. It can cause very bad health problems that may not go away, and sometimes death. Get medical help right away if you have signs like red, swollen, blistered, or peeling skin (with or without fever); red or irritated eyes; or sores in your mouth, throat, nose, or eyes.
- Diarrhea is common with antibiotics. Rarely, a severe form called C diff–associated diarrhea (CDAD) may happen. Sometimes, this has led to a deadly bowel problem (colitis). CDAD may happen during or a few months after taking antibiotics. Call your doctor right away if you have stomach pain, cramps, or very loose, watery, or bloody stools. Check with your doctor before treating diarrhea.
- If you are 65 or older, use Rifamate (rifampin and isoniazid) with care. You could have more side effects.
- Birth control pills and other hormone-based birth control may not work as well to prevent pregnancy. Use some other kind of birth control also like a condom when taking Rifamate (rifampin and isoniazid).
- 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.
How is this medicine (Rifamate) best taken?
Use Rifamate (rifampin and isoniazid) as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take on an empty stomach. Take 1 hour before or 2 hours after meals.
- Take with a full glass of water.
- Keep taking Rifamate (rifampin and isoniazid) as you have been told by your doctor or other health care provider, even if you feel well.
- Do not take antacids within 1 hour before or 1 hour after taking Rifamate (rifampin and isoniazid).
What do I do if I miss a dose?
- Take a missed dose as soon as you think about it.
- 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.
What are some side effects that I need to call my doctor about right away?
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 lupus like a rash on the cheeks or other body parts, sunburn easy, muscle or joint pain, chest pain or shortness of breath, or swelling in the arms or legs.
- Signs of a pancreas problem (pancreatitis) like very bad stomach pain, very bad back pain, or very bad upset stomach or throwing up.
- Signs of too much acid in the blood (acidosis) like confusion; fast breathing; fast heartbeat; a heartbeat that does not feel normal; very bad stomach pain, upset stomach, or throwing up; feeling very sleepy; shortness of breath; or feeling very tired or weak.
- Dizziness or passing out.
- Flu-like signs.
- Swollen gland.
- Joint pain or swelling.
- Muscle pain or weakness.
- Shortness of breath.
- Chest pain.
- Sweating a lot.
- A heartbeat that does not feel normal.
- Period (menstrual) changes.
- Fever, chills, or sore throat; any unexplained bruising or bleeding; or feeling very tired or weak.
- Purple spots or redness of the skin.
- A burning, numbness, or tingling feeling that is not normal.
- Feeling confused, not able to focus, or change in behavior.
- Memory problems or loss.
- Change in eyesight, eye pain, or very bad eye irritation.
- Change in balance.
- Change in tooth color. These changes may be long-lasting.
What are some other side effects of Rifamate?
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:
- Change in color of body fluids to orange or red.
- Stomach pain or diarrhea.
- Stomach cramps.
- Upset stomach or throwing up.
- Feeling sleepy.
- Feeling tired or weak.
- Not hungry.
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 the FDA at 1-800-332-1088. You may also report side effects at https://www.fda.gov/medwatch.
If OVERDOSE is suspected:
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.
How do I store and/or throw out Rifamate?
- Store at room temperature.
- 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.
Consumer Information Use and Disclaimer
- 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. Check with your pharmacist. If you have any questions about Rifamate (rifampin and isoniazid), please talk with your doctor, nurse, 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.
More about Rifamate (isoniazid / rifampin)
- Check interactions
- Compare alternatives
- Drug images
- Side effects
- Dosage information
- During pregnancy
- Drug class: antituberculosis combinations
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