Bio-Hirudin produced by PR Farmagro (M) S/B is the strongest natural anti-thrombin and was also named and classified as a thrombin inhibitor. Natural hirudin has an obvious advantage on the anticoagulation drugs for it has the double functions of anticoagulation and anti-thrombus simultaneously. Natural Hirudin is always beyond the recombinant-hirudin and needed by medical industries, healthcare etc.