Thrombin (Thrombinum) is a natural component of the blood coagulation system, which is formed in the body from prothrombin . For use in medical practice is obtained from donor human blood. Thrombin solution is applied topically to stop bleeding from capillaries and parenchymatous organs (during cranio-cerebral operations, operations on the liver, kidneys and other parenchymatous organs, bleeding from the bone cavity, gums, etc.). When bleeding from large vessels, thrombin is not used. A solution of thrombin is impregnated with a sterile fibrin sponge or gauze swab, which is applied to the bleeding wound. Introduction into the vein and into the muscles is not allowed. Product: hermetically sealed vials containing thrombin in an amount corresponding to 125-625 units. activity. The label indicates the number of doses (1 dose corresponds to 125 units of activity). See also Hemostatic agents.