Toxicity of Heparin

Abstract

Heparin is one of the oldest anticoagulants used in medical practice. It is a glycosaminoglycan with a large molecular size and a highly negative charge structure. Because of these properties, heparin is poorly absorbed from the gastrointestinal tract. Consequently, heparin must be administered parenterally. Heparin binds to antithrombin III (ATIII) and inhibits clotting factor activity, thus causing the process of inhibiting blood clot formation. Bleeding is an important side effect of heparin. Heparin overdoses can cause death in rare cases. However, if it occurs, the patient should be evaluated for the severity of bleeding and appropriately monitored for activated partial thromboplastin time with discontinuation of heparin. Then provide symptomatic and supportive treatments. Some cases need a heparin antidote named protamine, especially when there is significant bleeding. The dose of protamine requires an appropriate dose calculation by determining the amount of heparin expected to be found in blood along with closely monitoring hypotension and allergic reactions while receiving protamine.