Endogenous factors and drugs that directly inhibit the action of THROMBIN, usually by blocking its enzymatic activity. They are distinguished from INDIRECT THROMBIN INHIBITORS, such as HEPARIN, which act by enhancing the inhibitory effects of antithrombins.

Synonyms: 0, Direct Antithrombin, Antithrombin, Direct, Direct Antithrombins, Direct Thrombin Inhibitors, Antithrombins, Direct Thrombin Inhibitor, Thrombin Inhibitors, Direct, Thrombin Inhibitor, Direct, Inhibitor, Direct Thrombin, Antithrombins, Direct, Antithrombin