Increased serum conc w/ strong CYP3A4 inhibitors (eg, ketoconazole, clarithromycin, indinavir, itraconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, troleandomycin, voriconazole, & grapefruit juice). Decrease serum conc w/ strong CYP3A4 inducers (eg, rifampin, carbamazepine, phenobarb, phenytoin, rifabutin, rifampicin, & St. John's Wort). May increase plasma conc of co-administered substrates of P-gp (eg, digoxin, dabigatran, colchicine, pravastatin) or BCRP (eg, methotrexate, rosuvastatin, sulfasalazine).