We evaluated the efficacy of tissue plasminogen activator in treating experimental suprachoroidal hemorrhage. Suprachoroidal hemorrhage was created in 30 white rabbit eyes by implanting four pieces of small, exogenously formed blood coagula into the suprachoroidal space. Animals were randomized for treatment with a surgical sponge soaked in 25, 50, or 75 microg of tissue plasminogen activator (tPA) or balanced salt solution (BSS) as a control. The time when initiation and completion of clot dissolution occurred was established, and histological examination was performed to assess damage. Clot dissolution started within 30 min in the 50- and 75-microg tPA group, whereas it took 2.75 days in the control group; complete dissolution of blood clots took 4.5 h in the 75-microg tPA group and 14 days in the control group. Histological examination revealed a minimal change in photoreceptors within 6 h after treatment with 75 microg tPA. Treatment of suprachoroidal hemorrhage with tPA seems to be effective, but further investigations for determining the effective and nontoxic dose are required.