Heparin is an anticoagulant that prevents the formation of blood clots. It is used for both the prevention and treatment of thrombotic events, such as deep vein thrombosis and pulmonary embolism, as well as atrial fibrillation. It is also used to prevent excess coagulation during procedures such as extracorporeal circulation and cardiac surgery replacement therapy. It is given subcutaneously and intravenously. There are different types of heparin products, such as low-molecular-weight heparin, unfractionated heparin, and ultra-low molecular-weight heparin, available in the market.