Drug Interaction Report

Consumer information for this interaction is not currently available.

MONITOR: Coadministration with rifapentine may decrease the plasma concentrations of drugs that are substrates of the CYP450 2C8, 2C9, and/or 3A4 isoenzymes. The mechanism is accelerated clearance due to induction of these isoenzymes by rifapentine. Enzyme activities may be induced within 4 days of the first dose and return to normal 14 days after discontinuation of rifapentine. In vitro and in vivo enzyme studies have suggested rifapentine induction potential to be less than that of rifampin but greater than that of rifabutin. In addition, the magnitude of induction is dependent on dose and dosing frequency.

MANAGEMENT: The possibility of a diminished therapeutic response to drugs that are known substrates of CYP450 2C8, 2C9, and/or 3A4 should be considered during coadministration with rifapentine. Dosage adjustments as well as clinical and laboratory monitoring may be appropriate for some drugs, particularly those with a narrow therapeutic range, whenever rifapentine is added to or withdrawn from therapy.

Food enhances the absorption of rifapentine and may reduce the incidence of stomach upset, nausea, and/or vomiting. However, if rifapentine is part of a combination product, the recommendations may differ. Talk to your healthcare provider if you have any questions or concerns. It is important to tell your doctor about all other medications you use, including vitamins and herbs. Do not stop using any medications without first talking to your doctor.