Increased plasma conc w/ strong CYP3A inhibitors eg, certain antivirals (indinavir, nelfinavir, ritonavir, saquinavir), macrolides (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 effectiveness of CYP3A substrates w/ narrow therapeutic index eg, alfentanil, fentanyl, quinidine, cyclosporine, sirolimus, tacrolimus. Increased plasma conc of P-gp (eg, digoxin, dabigatran, colchicine, pravastatin), BCRP (eg, MTX, rosuvastatin, sulfasalazine), OCT1, MATE1 & MATE2K substrates.