The effect of prostaglandin F2 alpha on intraocular pressure in normotensive human subjects

Hypotensive and other ocular effects were studied for 24 hr after topical application of prostaglandin F2 alpha as the tromethamine salt (PGF2 alpha) in 45 normotensive human subjects. After baseline intraocular pressure (IOP) measurements, 62.5 micrograms, 125 micrograms and 250 micrograms of PGF2 alpha dissolved in 50 microliter of saline was applied to one eye of 15 subjects for each dose tested. Contralateral control eyes received 50 microliter of saline. As compared with the IOP of the contralateral control eyes, topical application of 62.5 micrograms PGF2 alpha caused a significant IOP reduction at 1-12 hr, with a maximal IOP reduction of 2.2 mm Hg at 2 hr. Treatment with 125 micrograms of PGF2 alpha lowered IOP significantly at 1-21 hr, with a maximal reduction of 3.1 mm Hg at 9 hr. Administration of 250 micrograms PGF2 alpha produced a significant reduction of IOP, which lasted for at least 24 hr. A maximal IOP reduction of 2.9 mm Hg occurred at 7 hr. Pupillary diameter was not altered. Aqueous flare and anterior chamber cellular response were not seen in any of the eyes of the subjects at any time after topical application of 62.5-250 micrograms PGF2 alpha. The drug caused side effects consisting of reddened skin of lower lid, ocular irritation, conjunctival hyperemia and headache.