Low Molecular Weight Heparin (LMWH)

Low molecular weight heparin (LMWH) is a class of medication used as an anticoagulant in diseases that feature thrombosis, as well as for prophylaxis in situations that lead to a high risk of thrombosis.

Because it can be given subcutaneously and does not require aPTT monitoring, LMWH permits outpatient treatment of conditions such as deep vein thrombosis (DVT) or pulmonary embolism (PE) that previously mandated inpatient hospitalization for unfractionated heparin (UFH) administration.

Because LMWH has more predictable pharmacokinetics and anticoagulant effect, LMWH is recommended over UFH for patients with massive pulmonary embolism and for initial treatment of deep vein thrombosis.

The use of LMWH needs to be monitored closely in patients at extremes of weight or in patients with renal dysfunction. An anti-factor Xa activity may be useful for monitoring anticoagulation, but the timing of the test needs to be coordinated with the laboratory. Given its renal clearance, LMWH may not be feasible in patients that have end-stage renal disease.

LMWH Information

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