RESUMO
A study was carried out on ocular and systemic absorption after topical application of 2% cyclosporin A in patients requiring corneal transplants, determining by polarized light immunofluorescence the levels of this drug in the cornea, aqueous humor and blood. Between 30 and 85 minutes after the last application, considerable levels of cyclosporin A were found in the explanted cornea (236 +/- 42 ng/mL). Relatively lower levels were found in the aqueous humor although there were significant differences between the patients who received a total topical dosage of 5 mg (16.92 +/- 6.86 ng/mL) and those who received 10 mg (25.06 +/- 9.13 ng/mL) over the same period of time. No analytically detectable levels were found in the plasma. We consider that topically administered cyclosporin A can reach immunosuppressive levels of activity in some ocular compartments thus eliminating the potential systemic effects resulting from its utilization by general administration.