The overall goal of this clinically focused pilot study was to investigate the preoperative benefit of oral administration of Yunnan Baiyao (YB) to Ehrlichia. canis, Anaplasma platys and/or heartworm seropositive canines. A total of 12 clinically normal dogs undergoing sterilization procedures were randomly subdivided into Control/Placebo Group (n=6) or Treatment Group (n=6). Each patient received three oral doses of YB (0.5g/5kg) or placebo every twelve hours with the last dose given the evening before surgery. Citrated blood measurements for prothrombin time (PT), activated partial thromboplastin time (aPTT), and fibrinogen were obtained before the first YB dose and after the third dose. Intraoperative blood loss was estimated by blood-soaked gauze sponge counts. The study found the Control Group’s mean aPTT increased by 3.8% while the Treatment Group’s decreased by 0.42%. PT values were slightly decreased in both groups. Fibrinogen decreased in controls (9.7%) but had a modest increase in treated dogs (12.4%). Intraoperative blood loss was increased in controls (3%) compared to the Treatment Group (mean±SD: 6.6±6.8 vs. 6.4±3.6, respectively). Findings from the study which suggest preoperative benefits from YB administration to seropositive dogs include stabilizing aPTT and fibrinogen values along with reduced intraoperative blood loss in YB treated dogs. Although these modest findings were not statistically significant in this small study, the biological trends suggest potential benefits of preoperative administration of YB before routine elective surgeries in seropositive patients and support a clinical trial with larger sample size.