- Current use or anticipated need for treatment with drugs that are known potent cytochrome P450, family 3, subfamily A, polypeptide 4 (CYP3A4) inhibitors (i.e., grapefruit juice, verapamil, ketoconazole, miconazole, itraconazole, erythromycin, telithromycin, clarithromycin, indinavir, saquinavir, ritonavir, nelfinavir, lopinavir, atazanavir, amprenavir, fosamprenavir and delavirdine)