Gemfibrozil-warfarin drug interaction resulting in profound hypoprothrombinemia.

The following describes a patient on a stable regimen of warfarin who developed severe hypoprothrombinemia and bleeding 4 weeks after starting gemfibrozil. Despite a warning by the manufacturer, only one report of this interaction has been published in the literature. This interaction may be overlooked by clinicians, which may result in a serious bleeding risk for patients on warfarin.