Maybe the most popular treatment for ED (thanks to some extent to Senator Bob Dole) is siledenafil which is ordinarily known as Viagra. Viagra functions as a PDE5 inhibitor, which makes the smooth muscle in the penis unwind and load up with blood. Since the appearance of the little blue marvel pill (Viagra) other doctor prescribed drugs including Levitra and Cialis have additionally made to the market. Obviously, the issue with ED is that most men really prefer not to discuss it, even with a clinical expert, and in this way neglect to seek treatment for it.