Drug Interaction Report

MONITOR: Coadministration with inducers of CYP450 2C9 may decrease the plasma concentrations of celecoxib, which is primarily metabolized by the isoenzyme. When a single 200 mg dose of celecoxib was administered to 12 healthy volunteers following pretreatment with the moderate CYP450 2C9 inducer rifampin 600 mg once daily for 5 days, celecoxib peak plasma concentration (Cmax) and systemic exposure (AUC) decreased by 56% and 64%, respectively, while clearance increased by 185%. Reduced efficacy of celecoxib may occur.

MANAGEMENT: The potential for diminished pharmacologic effects of celecoxib should be considered during coadministration with CYP450 2C9 inducers. Dose adjustments or alternative treatments may be required if an interaction is suspected.