60 patients undergoing unilateral total knee arthroplasty were randomized to receive either an intra-articular tranexamic acid injection or a saline injection immediately after skin closure. The purpose of this study was to determine the safety and efficacy of tranexamic acid without drainage in these patients over 5 days after surgery. The results indicated a significant reduction in total blood loss and blood transfusion requirements in the tranexamic group compared to the control group over the first 5 postoperative days. Complication rates were similar among groups, and red blood cell, hemoglobin, and hematocrit levels were significantly higher in the tranexamic group at 5 days postoperatively.