Increased cisapride & terfenadine plasma levels. Decreased astemizole clearance. Inhibition of pimozide, quinidine, carbamazepine, losartan metabolism. Increased risk of cardiotoxicity w/ erythromycin. Increased plasma conc by hydrochlorothiazide. Decreased AUC & shorter t½
w/ rifampicin. Increased plasma conc of other CYP2C9, CYP2C19 & CYP3A4 metabolized compd; halofantrine, sirolimus, tacrolimus. Reduced clearance, distribution vol & t½
of alfentanil. Increased amitriptyline & nortriptyline effects. Increased prothrombin time w/ warfarin. Increased conc & psychomotor effects in midazolam. Increased AUC of triazolam, celecoxib, cyclosporine, saquinavir, voriconazole, zidovudine. Increased systemic exposure of Ca-channel blockers, tofacitinib. Increased serum bilirubin & creatinine w/ cyclophosphamide. Delayed fentanyl elimination. Increased risk of myopathy & rhabdomyolysis w/ HMG-CoA reductase inhibitors. Enhanced serum conc of methadone. Potentially increased systemic exposure of NSAIDs metabolized by CYP2C9 eg, naproxen, lornoxicam, meloxicam, diclofenac. Inhibits hepatic metabolism of phenytoin. Increased metabolism of prednisone. Increased serum levels of rifabutin, vinca alkaloids eg, vincristine & vinblastine. Prolonged serum t½
of oral sulfonylureas eg, chlorpropamide, glibenclamide, glipizide, tolbutamide. Decreased mean plasma clearance rate of theophylline.