Low-molecular-weight heparin

Low-molecular-weight heparin (LMWH) is a class of anticoagulant medications. They are used in the prevention of blood clots and treatment of venous thromboembolism (deep vein thrombosis and pulmonary embolism) and in the treatment of myocardial infarction.

History

LMWHs were first derived from unfractionated heparin in the late 1970s. They have predictable pharmacokinetics and a lower risk of bleeding compared to unfractionated heparin, and can be administered once or twice daily.

Medical uses

LMWHs are used in the prevention and treatment of deep vein thrombosis, pulmonary embolism, and in the treatment of myocardial infarction. They are also used in the prevention of clotting during dialysis and in the prevention of clotting in the extracorporeal circuit during cardiac surgery.

Mechanism of action

LMWHs bind to the enzyme inhibitor antithrombin III (ATIII). The LMWH/ATIII complex in turn binds to and inactivates thrombin and factor Xa, two key components involved in blood coagulation.

Side effects

The most common side effect of LMWHs is bleeding. Other side effects can include heparin-induced thrombocytopenia (HIT), hypersensitivity reactions, skin necrosis, and osteoporosis with long-term use.

See also

• Anticoagulant
• Heparin
• Deep vein thrombosis
• Pulmonary embolism
• Myocardial infarction

Low-molecular-weight heparin

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  Fraxiparine 0.4ml syringe on yellow background
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  Reduction reaction diagram
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  UA(2S)-GlcNS(6S) chemical structure