Polygonum bistorta contains phytochemical compounds that can affect coagulation. It is used as hemorrhoid for bleeding control in traditional medicine. For its in vivo evaluation, 35 mice were randomly divided into 5 groups (n = 7) as well as the negative and positive control. On the 13th day of treatment, blood samples were collected for bleeding time (BT), clotting time (CT) and the number of platelets and on the 14th day, for prothrombin time (PT), activated partial thromboplastin time (aPTT). The results were shown although P. bistorta extract had a significant reducing effect on all coagulation tests in a dose-dependent manner, the greatest reduction in coagulation time (16.5 times) in the CT test and the best significant dosage is 1000 mg/kg/day shows that the P. bistorta extract has a greater effect on the common pathway than intrinsic and extrinsic pathways. تفاصيل المقالة