OBJECTIVETo determine the safety and efficacy of topical aminocaproic acid (Caprogel) in the management of traumatic hyphema.DESIGNMulticenter, randomized, double-masked, placebo-controlled clinical trial.PARTICIPANTSA total of 51 patients participated in this trial (power = 36%, 2-tailed test).INTERVENTIONPatients presenting with traumatic hyphema were randomly assigned to 5-day treatment with topical aminocaproic acid or a placebo gel. Patients were monitored daily with ocular examination and vital sign testing for the 5 days of treatment and at 24 and 48 hours after treatment. General physical examination and laboratory testing were performed at baseline and day 5.MAIN OUTCOME MEASURESThe main efficacy variable was the rate of rebleeding. Secondary efficacy variables included time to hyphema clearance, intraocular pressure, time to secondary hemorrhage, and visual acuity. Safety variables included adverse events, vital signs, and laboratory measurements.RESULTSRebleeding occurred in 30% of the placebo group (8 of 27; 95% confidence interval [CI] = 14-50%), versus 8% of the treatment group (2 of 24; 95% CI = 1-27%), for an estimated continuity-corrected difference in percentage of patients with bleeding of 17% (95% CI = -3-38%). Secondary efficacy variables were similar in the groups, except that there was a trend towards more visual improvement in the topical aminocaproic acid group (54%) than in the placebo group (30%) at the last measurement (P = 0.08). Adverse events were similar.CONCLUSIONSThis study provides evidence that topical aminocaproic acid is safe and demonstrates trends towards reducing the rebleeding rate in the management of traumatic hyphema. However, because the study was terminated before complete enrollment, more definitive recommendations will require a larger trial.