Latanoprost-d4 contains four deuterium atoms at the 3, 3′, 4, and 4′ positions. It is intended for use as an internal standard for the quantification of latanoprost by GC- or LC-mass spectrometry. Latanoprost is the isopropyl ester of 17-phenyl-13,14-dihydro prostaglandin F2α. 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.1,2,3 The EC50 value of latanoprost for (free acid) for FP receptors is 3.6 nM.4WARNING This product is not for human or veterinary use.