OBJECTIVE To evaluate the efficacy of tranexamic acid in reducing blood loss in total knee arthroplasty by examining the existing literature. METHODS This literature review investigated the use of tranexamic acid in knee arthroplasty. The search was performed in the Pubmed, Science Direct, Google Scholar, and Lilacs databases over a 20-year period using the keywords: "knee arthroplasty, tranexamic acid, and efficacy". Only randomized clinical trials published between 2000 and 2016 in English, Spanish, or Portuguese were accepted, and only trials which scored above 3 on the Jadad scale were selected. RESULTS A total of 7 randomized clinical trials met the inclusion criteria, with a sample of 948 patients. CONCLUSIONS The use of tranexamic acid in total knee arthroplasty (unilateral or bilateral) reduces perioperative and postoperative blood loss more than other available antifibrinolytics. With this reduction in total blood loss and the need for blood transfusions without any increase in side effects, the use of tranexamic acid can be considered safe and effective in controlling bleeding after knee arthroplasties. Level of Evidence II; Systematic review.