Effects of Heloderma suspectum venom on blood coagulation

The effect on blood coagulation of venom from the Gila monster Heloderma suspectum was studied in vivo and in vitro. Lethal and sublethal doses of venom failed to alter the clotting and prothrombin times of rabbit and cat blood in vivo. Venom mixed with freshly drawn blood from rabbits and cats had no effect on the clotting time. When venom was incubated with human, rabbit, and cat plasma for periods longer than 5 min, prothrombin time was prolonged. Placing venom in a boiling water bath for 15 min did not alter this.