What is the mechanism of action of Heparin?

Heparin is an anticoagulant that functions primarily by inhibiting the conversion of prothrombin to thrombin. This is a crucial step in the coagulation cascade, as thrombin is the enzyme responsible for converting fibrinogen to fibrin, leading to clot formation. By inhibiting thrombin, heparin effectively prevents the formation of fibrin clots, thus mitigating the risk of thrombus development.

The mechanism involves heparin binding to antithrombin III, which then accelerates the inactivation of thrombin and factor Xa, among other coagulation factors. This action significantly reduces blood coagulation, making heparin an effective agent in the prevention and treatment of venous thromboembolism and other clot-related disorders.