Increased clearance w/ phenytoin, barbiturates, primidone, carbamazepine, rifampicin, oxcarbazepine, topiramate, felbamate, griseofulvin & St. John's wort containing-products. Decreased steady state conc & systemic exposures w/ rifampicin. Increased or decreased plasma conc w/ HIV PIs & NNRTIs including combinations w/ HCV inhibitors. Increased plasma conc w/ strong CYP3A4 inhibitors. Increased AUC
(0-24h) w/ ketoconazole & erythromycin. May influence lab tests including biochemical parameters of liver, thyroid, adrenal & renal function, plasma levels of carrier proteins (eg, corticosteroid binding globulin & lipid/lipoprotein fractions), parameters of carbohydrate metabolism, & coagulation & fibrinolysis.