Effect of other drugs on celecoxib:
Celecoxib is mainly metabolized by CYP2C9, it should be used at half the recommended dose in patients treated with fluconazole. The concurrent use of a single dose of 200 mg of celecoxib 200 mg once daily of fluconazole, a potent inhibitor of CYP2C9, resulted in an average increase of 60% in Cmax and AUC 130% of celecoxib. Concomitant use of inducers of CYP2C9 such as rifampicin, carbamazepine and barbiturates may reduce plasma concentrations of celecoxib. It has not been observed to affect the pharmacokinetics of celecoxib with ketoconazole or antacids.