Parenteral administration of trypsin; clinical effect in 538 patients.

Intravenous administration of trypsin consistently produced fibrinolysis in recent dog and rabbit experiments. 1 This observation suggested that intravenous trypsin therapy might affect the fibrin network of human intra-vascular thrombi. Accordingly clinical studies were initiated, and we now report satisfactory results with trypsin in 71 of 74 patients with thrombophlebitis (63 patients receiving it intravenously and 11 intramuscularly). During treatment of these patients with trypsin it was apparent that the associated signs and symptoms of acute inflammation subsided and cleared up in two to three days, whereas lytic effects on the thrombi occurred much more slowly. This unexpected finding suggested that trypsin initiates biochemical reactions resulting in prompt and sustained subsidence of acute inflammation. Thrombolytic changes apparently occur later. It is the purpose of this paper to present clinical observations based on 6,456 trypsin infusions to 538 patients supporting the view that trypsin rapidly suppresses acute inflammation of diversified origin