Medically reviewed by A Ras MD.
What is rifapentine used for?
Rifapentine is a prescription medicine that is used to treat TB (tuberculosis).
PRIFTIN (rifapentine) for oral administration contains 150 mg of the active ingredient rifapentine per tablet.
The 150 mg tablets also contain, as inactive ingredients: calcium stearate, disodium EDTA, FD&C Blue No. 2 aluminum lake, hydroxypropyl cellulose, hypromellose USP, microcrystalline cellulose, polyethylene glycol, pregelatinized starch, propylene glycol, sodium ascorbate, sodium lauryl sulfate, sodium starch glycolate, synthetic red iron oxide, and titanium dioxide.
Rifapentine is a rifamycin derivative antimicrobial and has a similar profile of microbiological activity to rifampicin. The molecular weight is 877.04.
The molecular formula is C47H64N4O12.
The chemical name for rifapentine is rifamycin, 3-[[(4-cyclopentyl-1-piperazinyl)imino]methyl]- or 3-[N-(4-cyclopentyl-1-piperazinyl)formimidoyl] rifamycin or 5,6,9,17,19,21-hexahydroxy-23-methoxy-2,4,12,16,18,20,22-heptamethyl-8-[N-(4-cyclopentyl-l-piperazinyl)-formimidoyl]-2,7-(epoxypentadeca[1,11,13]trienimino)naphtho[2,1-b]furan-1,11(2H)-dione 21-acetate. It has the following structure:
Mechanism of Action
Rifapentine, a cyclopentyl rifamycin, is an antimycobacterial agent
Before taking rifapentine, tell your doctor:
- If you are allergic to rifapentine; any part of this medicine; or any other drugs, foods, or substances. Tell your doctor about the allergy and what signs you had.
- If you have porphyria.
- If you are breast-feeding or plan to breast-feed.
This is not a list of all drugs or health problems that interact with rifapentine.
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 rifapentine 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 rifapentine?
- Tell all of your health care providers that you take rifapentine. This includes your doctors, nurses, pharmacists, and dentists.
- This medicine may affect certain lab tests. Tell all of your health care providers and lab workers that you take rifapentine.
- Have blood work checked as you have been told by the doctor. Talk with the doctor.
- Do not skip doses. Skipping doses may cause rifapentine to not work as well. Other TB drugs may no longer work as well either.
- Take vitamin B6 (pyridoxine) as you were told by your doctor.
- This medicine may stain contact lenses.
- 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 rifapentine.
- Tell your doctor if you are pregnant or plan on getting pregnant. You will need to talk about the benefits and risks of using rifapentine while you are pregnant.
- This medicine may color breast milk an orange or red color. Talk with the doctor.
How is rifapentine best taken?
Use rifapentine as ordered by your doctor. Read all information given to you. Follow all instructions closely.
- Take with a meal.
- If you cannot swallow tablets, the tablet may be crushed and added to a small amount of soft food. Take the mixture right away. Do not store for future use.
- Keep taking rifapentine as you have been told by your doctor or other health care provider, even if you feel well.
What do I do if I miss a dose?
- 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.
What are the side effects of rifapentine that I need to call my doctor about immediately?
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, feeling tired, not hungry, upset stomach or stomach pain, light-colored stools, throwing up, or yellow skin or eyes.
- Fever, chills, or sore throat; any unexplained bruising or bleeding; or feeling very tired or weak.
- Chest pain or pressure.
- Fast or abnormal heartbeat.
- Dizziness or passing out.
- Flu-like signs. These include headache, weakness, fever, shakes, aches, pains, and sweating.
- Muscle pain.
- Eye redness.
- Shortness of breath.
- Swollen gland.
- 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.
What are some other side effects of rifapentine?
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:
- Not hungry.
- Joint pain.
- Upset stomach or throwing up.
- Change in color of body tissues like skin, teeth, or tongue or body fluids to orange or red.
- A long-lasting change in color of dentures.
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 rifapentine?
- Store at room temperature.
- Protect from heat.
- 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.
SRC: NLM .