Increased serum conc w/ strong CYP3A inhibitors (eg, clarithromycin, indinavir, itraconazole, ketoconazole, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, troleandomycin, voriconazole, & grapefruit juice). Decreased serum conc w/ strong CYP3A4 inducers (eg, carbamazepine, phenobarb, phenytoin, rifabutin, rifampicin, & St. John's Wort). Potential to increase plasma conc of P-gp substrates (eg, digoxin, dabigatran, colchicine, pravastatin) or BCRP substrates (eg, methotrexate, rosuvastatin, sulfasalazine).