Aqueous concentration of tranexamic acid after 5% and 10% eyedrop administration

To determine whether topical tranexamic acid can provide acceptable therapeutic concentration in the aqueous humor.

A total of 47 patients with cataract as the sole eye disease who have been scheduled for cataract operation received one drop of tranexamic acid 5% solution at various time intervals prior to operation (from 15 minutes to 9 hours). Two patients received 10% solution of the drug. Paracentesis of the anterior chamber was done and the aqueous humor was aspirated in the operation room. The aqueous samples were analyzed using high-performance liquid chromatography method with the limit of quantification around 0.1 microg/mL. Systemic and ocular side effects were evaluated.

Aqueous concentrations of tranexamic acid was higher than 1.5 microg/mL up to 160 minutes after administration of a single drop of 5% solution of the drug and then declined to an average concentration of 1 microg/mL at 300 minutes which persisted up to 9 hours after administration.In two patients for whom a single drop of 10% tranexamic acid solution was used, aqueous concentrations of 2.72 and 2.90 microg/mL were detected 60 minutes after administration. None of the patients experienced ocular or systemic side effects.

Topical administration of tranexamic acid is effective in yielding therapeutic intraocular concentrations of drug without any ocular or systemic toxicity.