Tranexamic acid tablets. Tablets of tranexamic acid, marketed as Cyclokapron, and their packaging. This drug is used to treat haemophilia, a genetic disorder that prevents the proper clotting of blood, and menorrhagia, abnormally heavy menstruation. Tranexamic acid is an antifibrinolytic drug, that is, it prevents the breakdown of fibrin, a protein that is important in the coagulation of blood. It also inhibits the activation of plasminogen to plasmin, an enzyme that breaks down fibrin.