Decreased absorption of ketoconazole, itraconazole & erlotinib. Increased absorption of digoxin. Decreased serum levels of atazanavir & nelfinavir. Increased plasma conc of diazepam, citalopram, imipramine, clomipramine & phenytoin. Increased C
max & AUC of cilostazol & cisapride. Elevated INR w/ warfarin & other coumarine derivatives. Decreased exposure to the active metabolite of clopidogrel. Decreased serum levels w/ CYP2C19 or CYP3A4 inducers (eg, rifampicin & St. John's wort).