[Effects of pre-instilled mydriatics on the intraocular concentration and anti-inflammatory action of topical 0.1% pranoprofen (3)--study on permeability factor].

The authors studied a mechanism of an increase in intraocular concentration of topical 0.1% pranoprofen (PPF) induced by pre-instilled mydriatics (0.5% tropicamide and 0.5% phenylephrine) in rabbit eyes. Ingredient solutions of mydriatics were instilled 60 minutes prior to instillation of PPF. The PPF concentrations in the cornea, aqueous humor and iris-ciliary body did not increase with pre-instilled benzalkonium chloride, chlorobutanol and tropicamide. The PPF concentrations were increased by pre-instilled phenylephrine (PHE), and the concentrations were 2 to 3 times higher than those without mydriatics. The PHE concentration in the aqueous humor was increased about 3 times in the presence of PPF. The octanol/water partition coefficient of PPF was increased in the presence of PHE. These data indicate that the increase of intraocular PPF concentration by the pre-instilled mydriatics was caused by PHE, and the enhancement of transcorneal permeability to PPF may have resulted from the formation of ion-pair complexes between PPF, an anionic drug, and PHE, a cationic drug.