The aim of this randomized controlled trial was to evaluate the effect of tranexamic acid (TXA) on postoperative blood loss during transurethral resection of the prostate (TURP) for benign prostatic hyperplasia (BPH). A total of 60 patients with BPH and undergoing TURP were randomized into TXA and control groups. Patients were intravenously administered 1 g TXA or placebo (0.9% sodium
chloride solution), respectively, after the induction of anesthesia for TURP. Intraoperative and postoperative bladder irrigation volumes and blood loss volumes were compared between the two groups. Coagulation function (measured by prothrombin, activated partial thromboplastin and thrombin time and fibrinogen levels) was measured before the operation and at 4 h post-operation. Complications from thromboembolic events, such as lower-limb and pulmonary embolisms, were also noted. The TXA group had significantly decreased blood loss intraoperatively and at 4 h postoperatively compared with the control group (P<0.05). The 24 h postoperative blood loss and coagulation function of the two groups were not significantly different. No thromboembolic events or other complications occurred in either group. In conclusion, a preoperative single dose of TXA was indicated to reduce perioperative blood loss in TURP without a notable increase in thrombosis risk.