Description: Epsilon-aminocaproic acid (EACA) is an inhibitor of fibrinolysis. This hemostatic agent is indicated in the treatment of systemic or urinary hyperfibrinolysis, such as may be encountered with disorders such as aplastic anemia, abruptio placentae, hepatic cirrhosis, neoplastic disease such as carcinoma of the prostate, lung, stomach, or cervix, and following cardiac surgery (with or without by-pass procedures.) Investigational uses include treatment of oral bleeding associated with dental extraction in hemophiliacs (oral or topical administration), to reduce post-surgical bleeding complications in patients undergoing cardiopulmonary by-pass procedures (CPB) (intravenous administration), and for use as a bladder irrigant (intravesical administration). Although EACA has been successfully used prophylactically for patients undergoing CPB procedures,[1116] it has not been determined whether it is as effective as aprotinin. Despite its relatively short half-life necessitating frequent administration, EACA has a considerable cost advantage over aprotinin. EACA was approved by the FDA in 1964 and can be administered orally or intravenously. In 1995, it received orphan drug designation as a topical treatment of traumatic hyphema, however, a formulation for this use is currently unavailable.

Mechanism of Action: Aminocaproic acid binds to lysine-binding sites within the plasminogen/plasmin molecule. This interferes with the ability of plasmin to lyse fibrin clots. Low concentrations of EACA inhibit in vitro profibrinolysin activation by streptokinase and urokinase. Aminocaproic acid may suppress chymotrypsin proteolytic enzymes and antigen-antibody reactions. Aminocaproic acid does not alter the concentrations of clotting factors. EACA diminishes the tuberculin reaction in patients sensitive to tuberculin. The antihistaminic action of this agent is not clinically significant.

Pharmacokinetics: Aminocaproic acid is available in oral and parenteral formulations. The drug is rapidly absorbed following oral administration, with peak plasma concentrations attained in less than 2 hours. Plasma concentrations are increased in patients with severe renal dysfunction, but dosage adjustments generally are not indicated. EACA is widely distributed to extravascular and intravascular compartments including red blood cells. It is unknown if EACA crosses the placenta or is distributed into breast milk. The elimination half-life is approximately 2 hours. EACA is excreted primarily in the urine, with 40—65% eliminated unchanged within 12 hours. Approximately 11% is eliminated as the metabolite adipic acid.

References
1116. Daily PO, Lamphere JA, Dembitsky WP et al. Effect of prophylactic epsilon-aminocaproic acid on blood loss and transfusion requirements in patients undergoing first-time coronary artery bypass grafting. J Thorac Cardiovasc Surg 1994;108:99—108.

Drug Information Provided by
Gold Standard, Inc. � 2007