- Patients requiring treatment interfering with CYP3A4 isoenzyme (rifampicin, rifabutin, carbamazepine, phenobarbital, phenytoin) or inhibiting CYP3A4 isoenzyme's activity (ketoconazole, voriconazole, itraconazole, telithromycin, clarithromycin, Diltiazem, Verapamil, nicardipine, clotrimazole, fluconazole , troleandomycin, bromocriptine, cimetidine, danazol, protease inhibitors) -patients requiring treatment by cisapride and metoclopramide