- Strong inhibitors of cytochrome P450 3A4 (CYP3A4), including some macrolide antibiotics (e.g., clarithromycin, erythromycin), cyclosporine, antiretroviral drugs (e.g., ritonavir, nelfinavir), and systemic azole antifungal agents (e.g., ketoconazole, itraconazole), and nefazodone