As with all anticoagulants, bleeding is the major adverse effect of tinzaparin. Hemorrhage may occur at virtually any site. Risk is dependent on multiple variables. In case of overdose, discontinue medication, apply pressure to bleeding site if possible, and replace volume and hemostatic blood elements as required. If these measures are ineffective, or if bleeding is severe, protamine sulfate may be administered at 1 mg per every 100 anti-Xa int.
Thrombolytic agents increase the risk of hemorrhage.
Risk of bleeding may be increased during concurrent therapy. Heparin acts as an anticoagulant by enhancing the inhibition rate of clotting proteases by antithrombin III, impairing normal hemostasis and inhibition of factor Xa. Low molecular weight heparins have a small effect on the activated partial thromboplastin time and strongly inhibit factor Xa. The primary inhibitory activity of tinzaparin is through antithrombin. Tinzaparin is derived from porcine heparin that undergoes controlled enzymatic depolymerization.