Warfarin is an oral anticoagulant used to prevent and treat blood clotting disorders. It works by blocking the formation of vitamin K-dependent clotting factors, which helps reduce the likelihood of blood clots that can lead to serious health problems. Warfarin is usually prescribed for conditions such as preventing strokes in patients with atrial fibrillation, a heart rhythm disorder that increases the likelihood of clots.
Warfarin is also used to prevent blood clots from forming in the deep veins, a condition known as deep vein thrombosis, and to prevent these clots from traveling to the lungs, known as pulmonary embolism.