Nonetheless, because warfarin increases the risk of bleeding, blood tests
to measure the degree to which the blood
is anti-coagulated or thinned (prothrombin time; INR) may be ordered to assess the degree of blood-thinning when warfarin and clopidogrel are used together. The same enzyme also is responsible for
the metabolism of phenytoin (Dilantin), tamoxifen (Nolvadex), tolbutamide (Orinase), torsemide (Demadex), and fluvastatin (Lescol).