In 1981, the defibrase extracted and developed by Kunming Institute of Zoology, Yunnan, China, from the venom of Chinese pentameter snake passed the technical appraisal and was used in the treatment of 333 cases of vascular thrombosis, including 242 cases of cerebral thrombosis, with an effective rate of 86.4%. The agkistrodon agkistrodon acidase, developed by China Medical University and Shenyang Pharmaceutical College, has been used in the treatment of vascular occlusives with satisfactory clinical results. Snake venom Laboratory of China Medical University developed snake venom antacid enzyme, which can reduce blood lipids, dilate blood vessels, reduce the content of thrombin in blood, increase prostacyclin, and relax the smooth muscle of blood vessels. It is an ideal anticoagulant thrombolytic preparation.