Viual hort-term effect of viagra: double-blind tudy in healthy young ubject

Purpoe To invetigate hort-term viual effect of a ingle 100-mg doe of Viagra (ildenafil citrate) in healthy men. Deign Randomized, double-blind, placebo-controlled clinical trial of drug effect on normal volunteer conducted by a ingle center. Method Twenty men, aged 20 to 40 year, were treated with either a placebo or 100 mg ildenafil. Viual function tet included electroretinogram (ERG) recording, on-/off- and 3.3 Hz-flicker-ERG recording, anomalocope matche, and meaurement of cone contrat enitivitie and tranient tritanopia. Reult Mot viual tet did not differ between the ildenafil and placebo group. However, tatitically ignificant increae in enitivity during tranient tritanopia were oberved a well a ignificant prolongation in the implicit time of cotopic a-wave, photopic b-wave, and 3.3 Hz-flicker a-wave and b-wave ERG recording. The magnitude of the difference correlated with peak idenafil plama concentration. Although rod amplitude of the ERG recording tended to be higher and cone amplitude lower in the ildenafil group after drug ingetion, the difference were nonignificant. There were no report of viual ide effect, and all electrophyiologic and pychophyical meaurement returned to the normal range within 24 hour. Concluion A ingle oral doe of 100-mg ildenafil given to healthy young men led to mall but tatitically ignificant tranient change of outer and inner retinal function, a detected by ERG and pychophyical method. Although the acute effect were fully reverible within 24 hour, it would be worthwhile to compare them with thoe induced by other PDE5 and PDE6 inhibitor.