The Effect of Yunnan Baiyao on Platelet Activation, Buccal Mucosal Bleeding Time, Prothrombin Time, Activated Partial Thromboplastin Time, and Thromboelastography in Healthy Dogs: A Randomized, Controlled, Blinded Study

The purpose of this randomized, controlled, blinded, crossover study was to determine the effects of orally administered Yunnan Baiyao (100 mg/kg body weight) on tests of coagulation in dogs. Buccal mucosal bleeding time, prothrombin time, activated partial thromboplastin time, clotting parameters obtained from thromboelastography, and indices of platelet activation were determined before and after Yunnan Baiyao administration. Eight, adult dogs were randomly given either lactose or Yunnan Baiyao filled capsules. Jugular venous sampling and buccal mucosal bleeding time were performed before treatment (T=0), and then at 1, 3, and 12 hours after. Three weeks later the procedure was repeated to complete the crossover. Statistical analysis was performed using a mixed model ANOVA (P ≤0.05). In addition, percentage change from baseline was calculated for each parameter to evaluate trends that might be present in the small number of animals used in this study. Statistical results demonstrated none of the measured parameters were significantly different within groups or between groups at any time. Comparison of percentage change between placebo and Yunnan Baiyao groups demonstrated a trend at some sampling test points in the Yunnan Baiyao group towards decreased buccal mucosal bleeding times, increases in platelet number and plateletcrit along with TEG parameter changes (quicker clot intiation and rate of formation). In conclusion, under the conditions of this study, Yunnan Baiyao demonstrated non-significant differences between preand post-administration buccal mucosal bleeding times, platelet numbers and some TEG values along with no evidence of induction of hypercoagulability in healthy, non-bleeding dogs.