Increased plasma conc w/ strong CYP3A inhibitors [eg, certain antivirals (indinavir, nelfinavir, ritonavir, saquinavir), macrolide antibiotics (clarithromycin, telithromycin, troleandomycin), antifungals (ketoconazole, voriconazole), nefazodone]; moderate CYP3A inhibitors (eg, diltiazem, verapamil); grapefruit or grapefruit juice. Decreased plasma conc w/ strong CYP3A inducers (eg, rifampicin, carbamazepine, phenytoin, rifabutin, phenobarb, St. John's wort); moderate CYP3A inducers (eg, efavirenz, modafinil, bosentan, etravirine, nafcillin). Reduced plasma levels & efficacy of CYP3A substrates, especially those w/ narrow therapeutic index (eg, alfentanil, fentanyl, quinidine, cyclosporine, sirolimus, tacrolimus). Increased plasma conc of substrates of P-gp (eg, digoxin, dabigatran, colchicine, pravastatin), BCRP (eg, MTX, rosuvastatin, sulfasalazine), organic cation transporter 1 (OCT1), multidrug & toxin extrusion protein 1 (MATE1), & 2K (MATE2K).