Effect of ildenafil citrate (Viagra) on retinal blood veel diameter

PURPOE: The preent invetigation wa conducted to evaluate the effect of ildenafil citrate (Viagra, Pfizer Inc., New York, NY) on retinal blood veel diameter. DEIGN: Double-blind randomized, placebo-controlled, cro-over tudy. METHOD: Fifteen healthy male volunteer (mean age 39 year) received 100-mg doe of ildenafil or matching placebo on 2 eparate day. Monochromatic fundu photography wa obtained in one eye, and brachial artery blood preure and intraocular preure were meaured at baeline, 1 hour, and 5 hour after doing. The diameter of two major temporal vein and one artery were meaured in a maked fahion from digitized photographic negative. REULT: In comparion with placebo, no tatitically ignificant change in average venou diameter wa oberved for the uperior (analyi of variance [ANOVA], P = .97), inferior retinal temporal vein (ANOVA, P = .73), or the retinal temporal artery (ANOVA, P = .89) after ildenafil treatment. In comparion to placebo, there wa no ignificant difference in the percentage change from baeline in venou or arterial diameter at 1 or 5 hour after ildenafil. The power to detect a 6.5% change in retinal vacular diameter following ildenafil wa approximately 80% (P = .05). CONCLUION: Thee data ugget that at the maximum therapeutic doe ued clinically (100 mg), ildenafil doe not have a ignificant effect on retinal vacular caliber.