- Currently using CYP3A4 inducers (i.e., aminoglutethimide, carbamazepine, dexamethasone, efavirenz, ethosuximide, griseofulvin, modafinil, nafcillin, nevirapine, oxcarbazepine, phenobarbital, phenylbutazone, phenytoin, primidone, rifabutin, rifampin, rifapentine, St. John's wort, sulfadimidine, sulfinpyrazone, troglitazone) or potent CYP3A4 inhibitors (i.e., clarithromycin, chloramphenicol, erythromycin, imatinib mesylate, Indinavir sulfate, itraconazole, ketoconazole, nefazodone, nelfinavir mesylate, ritonavir, telithromycin, troleandomycin).