Both Heparin and Warfarin are used to treat deep vein thrombosis (DVT) or known as the blood clots in the leg veins, pulmonary embolism or the blood clots in the lungs and atrial Fibrillation or irregular heartbeat.
They are simply called anticoagulants, which are commonly called blood thinners that decrease the clotting ability of the blood and prevent growth of a clot.
Moreover, Heparin is naturally occurring that prevents formation of clot and extension of the clotting that provide immediate response within 20 to 60 minutes after administration and last for 8 to 12 hours.
Meanwhile, Warfarin is a vitamin k antagonist that reduces the effect of vitamin k to manage clotting in 12 to 24 hours after taking it and remain in the body for 3 to 5 days.