indication

For prevention of deep vein thrombosis, which may result in pulmonary embolism, following knee surgery.

pharmacology

Ardeparin, an anticoagulant, is a fractionated heparin. It acts at multiple sites in the normal coagulation system to inhibit reactions that lead to the clotting of blood and the formation of fibrin clots both in vitro and in vivo.

mechanism of action

Ardeparin binds to antithrombin III, accelerating its activity in inactivating factor Xa and thrombin, thereby inhibiting thrombosis. Ardeparin also binds to heparin cofactor II, inhibiting thrombin. Ardeparin does not effect prothrombin time (PT) assays and may prolong activated partial thromboplastin time (APTT). Ardeparin has double the anti-factor Xa activity versus anti-factor IIa activity, compared to unfractionated heparin which has approximately equal anti-factor Xa activity and anti-factor IIa activity.

toxicity

Symptoms of overdose may include excessive bleeding and bruising.

biotransformation

Liver and the reticulo-endothelial system are the sites of biotransformation.

absorption

Well absorbed following subcutaneous administration, with a mean bioavailability of 92% (based on anti-factor Xa activity).

half life

Elimination half-life for anti-factor Xa activity averages 3.3 hours following a single intravenous dose, while elimination half-life for anti-factor IIa activity averages 1.2 hours following a single intravenous dose.