<unk>  is metabolized by cytochrome P450 3A4, so substances that inhibit or activate CYP3A4 can strongly effect how much<unk>  is present. CYP3A4 inhibitors, which increase the amount of<unk>  available per dose, include cimetidine, erythromycin, itraconazole, ketoconazole, HIV protease inhibitors, and grapefruit juice. CYP3A4 activators, which decrease the amount of<unk>  available per dose, include phenytoin, carbamazepine, rifampicin, barbiturates, efavirenz, nevirapine, and Saint John's wort.
Felodipine
Amlodipine
Cyclothiazide
Chlorothiazide
Telmisartan
Hydrochlorothiazide
Olmesartan
Azilsartan