Enhanced effects of vit K antagonists & increased risk of bleeding. Fenofibrate: Reversible paradoxical reduction of HDL-C w/ glitazones. Simvastatin: Increased risk of myopathy & rhabdomyolysis w/ CYP3A4 inhibitors eg, itraconazole, ketoconazole, posaconazole, erythromycin, clarithromycin, telithromycin, HIV PIs (eg, nelfinavir), nefazodone; fluconazole; danazol; ciclosporin; amiodarone, amlodipine, diltiazem, verapamil; gemfibrozil, other fibrates, statins; daptomycin; niacin (≥1 g/day); fusidic acid; colchicine. Increased plasma conc & risk of myopathy w/ BCRP inhibitors (eg, elbasvir & grazoprevir). Increased plasma exposure w/ grapefruit juice. Interfered metabolism w/ rifampicin.