Extreme Elevation of the Prothrombin Time-International Normalized Ratio due to a Probable Interaction between Warfarin and Flutamide

Flutamide, a chemotherapeutic agent for prostate cancer, is known to enhance warfarin anticoagulation. However, not much is known about its pharmaceutical interaction. We herein report the case of a patient with an implanted pacemaker for atrial fibrillation with bradycardia who was on warfarin. This patient presented with deterioration of hematuria, gingival, ear, and subcutaneous bleeding. The prothrombin time-international normalized ratio...