In order to avoid the side effects and drawbacks of intravenous injection of vasoactive drugs, we evaluated the use of transcutaneous nitroglycerin, a powerful smooth muscle relaxant, in enhancing the quality of erection. In this study, 26 impotent patients were treated with (nitroglycerin or placebo) patches applied to the skin of the penile shaft. A positive response was reported by 21 patients and 17 men out of the 21 were able to distinguish a marked difference between the nitroglycerin and placebo patches. These results indicate that nitroglycerin patches have to be tried, especially in patients with moderate erection disturbances.