Latanoprost is the isopropyl ester of 17-phenyl-13,14-dihydro PGF2α. It is a prodrug form of the free acid, which is a potent agonist of the FP receptor in the eye. Latanoprost reduces intraocular pressure in glaucoma patients with few side effects.{4697,3802,5338} The EC50 value of latanoprost (tested as the free acid) for FP receptors is 3.6 nM.{1107}