PGF2α isopropyl ester is an ester prodrug of PGF2α with enhanced lipid solubility. Due to better membrane penetration, PGF2α isopropyl ester is more suitable than PGF2α or PGF2α tromethamine salt for topical application in studies on intraocular pressure. The ester functionality is readily hydrolyzed in vivo to release the active compound PGF2α. When administered topically to the eyes of cynomolgus monkeys, a 5 µg dose reduces intraocular pressure by 68% after the fourth day of treatment.