Heparin is the anticoagulant most widely used to prevent clotting in the extracorporeal blood circuit in haemodialysis patient. Heparin is a highly anionic-charged, sulphated glycosaminoglycan that is extracted from bovine and porcine lung or intestine. It accellerates the formation of a molecular complex between antithrombin III, a constituent of normal plasma, and coagulation factors of the intrinsic coagulation system