Viagra shows no effect on ocular circulation

THOROFARE, N.J. — Patients treated with sildenafil citrate, marketed by Pfizer as Viagra, had no significant change in blood flow to the optic nerve rim or choroid, according to researchers in Philadelphia. Additionally, Viagra did not produce significant changes in intraocular pressure, ocular perfusion pressure or systemic blood pressure.

These findings may have implications for glaucoma patients taking Viagra, the researchers said.

Fifteen healthy men, aged 30 years or older, with a visual acuity of 20/25 or better, were included in a randomized, double-masked, placebo-controlled crossover study. Patients had normal eye examinations, and an intraocular pressure (IOP) of 21 mm Hg or less. The study was instigated because sildenafil has not only vasodilatory properties, but "a somewhat lower affinity for phosphodiesterase type 6, an important component of the phototransduction cascade," said Juan E. Grunwald, MD, and colleagues in their study.

Results indicated no significant change in the mean foveolar choroidal blood flow after sildenafil treatment. Researchers also found no significant change in mean optic nerve blood flow in Viagra patients. When compared with the placebo group, the Viagra patients had no significant change in IOP, mean blood pressure or perfusion pressure, according to the study.

For more of this article, from the upcoming Nov. 1 issue of Ocular Surgery News, click here.