tenecteplase + unfractionated heparin

**Tenecteplase + unfractionated heparin** is a combination therapy composed of tenecteplase, a fibrinolytic agent (recombinant tissue plasminogen activator; TNK-tPA), and unfractionated heparin (UFH), an anticoagulant. Tenecteplase acts by binding to fibrin in a thrombus and converting the entrapped plasminogen to plasmin, leading to local fibrinolysis of clots. Unfractionated heparin potentiates the activity of antithrombin III, inhibiting thrombin (factor IIa) and factor Xa, and preventing new clot formation.\nThis combination is primarily used for the acute management of ST-elevation myocardial infarction (STEMI) and is under investigation or in use for other indications such as acute pulmonary embolism and, more recently, for thrombosis associated with severe COVID-19[3][7]. The combination is given intravenously. While effective in preventing further clotting and in promoting the dissolution of thrombi, the regimen carries a risk of bleeding, including intracranial hemorrhage, particularly in elderly patients. An in vitro interaction has been reported where tenecteplase may attenuate the anticoagulant effect of UFH, but the clinical significance is not fully established[1].