Comparative corneal penetration of prednisolone sodium phosphate and prednisolone acetate in NZW rabbits

Comparative corneal penetration studies in the literature with prednisolone sodium phosphate solution and prednisolone acetate suspension administered to rabbit eyes give conflicting results concerning the greater bioavailability of prednisolone acetate. A recent in vitro penetration study shows similar fluxes for both salt forms in terms of prednisolone, quantified by a specific HPLC assay. An in vivo comparison has been conducted in NZW rabbit eyes and shows similar bioavailability for both drugs. Prednisolone sodium phosphate, prednisolone acetate and the primary metabolite prednisolone are quantified by a specific HPLC assay in aqueous humor.