Rifapentine

Rifapentine is a prescription medication used for the treatment of pulmonary tuberculosis and latent tuberculosis. 

• Rifapentine is available under the following different brand names: Priftin

Adult and pediatric dosage

Tablet

• 150mg

Pulmonary Tuberculosis

Adult dosage

• Initial phase (2 months): 600 mg orally for 2 weeks for 2 months; an interval between doses not less than 3 days (in combination with other anti TB drugs) THEN
• Continuation phase (4 months): 600 mg orally every week for 4 months by direct observation therapy with isoniazid or another appropriate anti TB drug

Latent tuberculosis

Adult dosage

• Once weekly rifapentine orally (weight-based dosing below) plus isoniazid once-weekly for 12 weeks as directly observed therapy (DOT)
• Aged above 12 years and weighing above 50 kg: 900 mg
• Aged above 12 years and 32.1-50 kg: 750 mg
• Isoniazid dose: 15 mg/kg (rounded to nearest 50 mg or 100 mg); not to exceed 900 mg once-weekly for 12 weeks

Pediatric dosage

Aged less than 2 years: Safety and efficacy not established

2-11 years

• Once weekly rifapentine orally (weight-based dosing below) plus isoniazid once-weekly for 12 weeks as directly observed therapy (DOT)
• 10-14 kg: 300 mg
• Weight  above 14-25 kg: 450 mg
• Weight above 25-32 kg: 600 mg
• Weight above 32-49.9 kg: 750 mg
• Weight above 50 kg: Not to exceed 900 mg
• Isoniazid dose: 25 mg/kg (rounded to nearest 50 mg or 100 mg); not to exceed 900 mg once-weekly for 12 weeks

Dosage Considerations – Should be Given as Follows: 

• See “Dosages”

Common side effects of Rifapentine include:

• heartburn
• abdominal pain
• loss of appetite
• nausea
• vomiting
• yellowing skin and eyes (jaundice)
• gas (flatulence)
• cramps
• diarrhea
• elevated liver function test (LFT) results
• hepatitis
• deficiency of platelets in the blood
• discoloration of the skin
• brain bleed
• fatalities
• abnormal clotting of the blood
• destruction of red blood cells
• low red blood cell count
• headache
• fever
• drowsiness
• fatigue
• loss of full control of body movements
• dizziness
• inability to concentrate
• mental confusion
• behavioral changes
• muscular weakness
• pain in extremities
• generalized numbness
• visual disturbances
• menstrual disturbances
• elevated BUN
• elevated serum uric acid
• flushing
• itching
• rash
• severe itching
• hives
• acute formation of blisters
• erythema multiforme, including Stevens-Johnson Syndrome
• toxic epidermal necrolysis
• inflammation in blood vessels
• eosinophilia
• sore mouth
• sore tongue
• pink eye
• acute allergic reaction (anaphylaxis)
• swelling
• flu syndrome
• shortness of breath
• wheezing
• decrease in blood pressure
• shock.

Serious side effects of Rifapentine include:

• watery or bloody diarrhea;
• liver problems--nausea, upper stomach pain, itching, tired feeling, loss of appetite, dark urine, clay-colored stools, jaundice (yellowing of the skin or eyes);
• low red blood cells (anemia)--pale skin, feeling light-headed or short of breath, rapid heart rate, trouble concentrating; or
• low white blood cell counts--fever, swollen gums, painful mouth sores, pain when swallowing, skin sores, cold or flu symptoms, cough, trouble breathing.

Rare side effects of Rifapentine include:

• blood in urine
• inflammation in the kidney
• lack of blood flow to the kidneys
• kidney insufficiency
• acute kidney failure
• psychoses
• the disease of muscle tissue
• adrenal insufficiency, Addison's Disease
• lowered white blood cell count

This is not a complete list of side effects and other serious side effects or health problems that may occur as a result of the use of this drug. Call your doctor for medical advice about serious side effects or adverse reactions. You may report side effects or health problems to FDA at 1-800-FDA-1088.

If your medical doctor is using this medicine to treat your pain, your doctor or pharmacist may already be aware of any possible drug interactions and may be monitoring you for them. Do not start, stop, or change the dosage of any medicine before checking with your doctor, health care provider, or pharmacist first.

• Rifapentine has severe interactions with at least 25 other drugs.
• Rifapentine has serious interactions with at least 138 other drugs.
• Rifapentine has moderate interactions with at least 193 other drugs.
• Rifapentine has minor interactions with at least 66 other drugs.

This information does not contain all possible interactions or adverse effects. Visit the RxList Drug Interaction Checker for any drug interactions. Therefore, before using this product, tell your doctor or pharmacist about all your products. Keep a list of all your medications with you and share this information with your doctor and pharmacist. Check with your health care professional or doctor for additional medical advice, or if you have health questions or concerns.

Contraindications

• Hypersensitivity to rifamycins

Effects of drug abuse

• None

Short-Term Effects

• See “What Are Side Effects Associated with Using Rifapentine?”

Long-Term Effects

• See “What Are Side Effects Associated with Using Rifapentine?”

Cautions

• Severe cutaneous adverse reactions (SCARs) such as Stevens-Johnson syndrome (SJS) and drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome have been reported in association with treatment regimens in patients with active and latent tuberculosis; discontinue therapy at the first appearance of skin rash, mucosal lesions, or any other sign of hypersensitivity
• May increase liver enzymes; initiation in patients with existing abnormal liver tests and/or liver disease only in cases of necessity and under strict medical supervision; monitor LFTs every 2-4 weeks and discontinue if evidence of liver injury occurs
• Hypersensitivity or anaphylaxis was reported including hypotension, urticaria, angioedema, acute bronchospasm, conjunctivitis, thrombocytopenia, neutropenia, or flu-like syndrome
• Not for use as initial phase treatment in HIV-infected individuals with active pulmonary TB
• A higher relapse rate may occur in patients with cavitary pulmonary lesions and/or positive sputum cultures after the initial phase of active TB treatment, and patients with bilateral pulmonary disease
• Induces CYP450 isoenzymes; coadministration with drugs metabolized by these enzymes (eg, protease inhibitors, certain NRTIs, hormonal contraception) may result in significantly decreased plasma concentrations and loss of therapeutic effect
• May produce a red-orange discoloration of body tissues/fluids (eg, skin, teeth, tongue, urine, feces, saliva, sputum, tears, sweat, CSF); contact lenses or dentures may become permanently stained
• As with the use of nearly all systemic antibacterial agents, Clostridium difficile-associated diarrhea (CDAD) was reported; discontinue if CDAD confirmed
• Porphyria reported in patients receiving rifampin, attributed to induction of delta amino levulinic acid synthetase; rifapentine may have similar enzyme induction properties; avoid in patients with a history of porphyria

Pregnancy & Lactation

• No adequate and well-controlled studies have been performed on pregnant women
• There are limited pregnancy outcome data reported from women enrolled in clinical trials of various rifapentine treatment regimens for active tuberculosis and latent tuberculosis infection
• Reported rate of spontaneous abortion following exposure did not represent an increase over the background rate of spontaneous abortion reported in the general population; further interpretation of these data is limited by the quality of clinical trial adverse event reporting
• When administered during the last few weeks of pregnancy, rifampin, another rifamycin product, increased the risk for postnatal hemorrhages in the mother and infant for which treatment with vitamin K may be indicated
• Contraception
• Therapy may reduce the efficacy of hormonal contraceptives; advise patients using hormonal contraceptives to use an alternative non-hormonal contraceptive method or add a barrier method of contraception during treatment
• Lactation
  • Unknown if excreted in human milk
  • May produce a red-orange discoloration of body fluids; potential for discoloration of breast milk
  • A slight increase in rat pup mortality was observed during lactation when dams were dosed late in gestation through lactation
  • A decision should be made whether to discontinue nursing or discontinue the drug, taking into account the importance of the drug to the mother
  • Monitor infants exposed to drugs through breast milk for signs of hepatotoxicity including irritability, prolonged unexplained crying, yellowing of the eyes, loss of appetite, vomiting, and changes in the color of urine (darkening) or stool (lightening, pale or light brown)