As blood flows into the penis, the corpora cavernosa swell, and this swelling compresses the veins (blood vessels that drain the blood out of the penis) against the tunica albuginea. Compression of the veins prevents blood from leaving the penis. This creates a hard erection. When the amount of cGMP decreases by the action of a chemical called phosphodiesterase type 5 (PDE5), the muscles in the penis tighten, and the blood flow into the penis decreases. With less blood coming into the penis, the veins are not compressed, allowing blood to drain out of the penis, and the erection goes down.
It's an all too common problem: Roughly half of men with diabetes—and up to 25 percent of men overall—experience erectile dysfunction (ED) at some point in their lives. And it's a complicated problem, too, with diverse physical origins and complex emotional ramifications. Yet diabetes-related ED needn't be a no-sex sentence for men. There are ways to avoid this disorder and to treat it at any age. While much of the research on ED is still in its infancy, here is what science has to say so far.
Researchers have found that one particular simple sugar, present in increased levels in diabetics, interferes with the chain of events needed to achieve and maintain erection and can lead to permanent penile impairment over time. The results, which have implications for new types of erectile dysfunction treatments targeting this mechanism of erection, are described in the August 16 issue of the Proceedings of the National Academy of Sciences.
In regard to circulation, alcohol causes the blood vessels to dilate, which influences the way the blood moves in and out of the penis. A good blood flow regulates the relaxation and contraction of the penis, so it can get and maintain an erection. Without it, no matter how much you may want it to happen differently, your penis will simply remain flaccid.
Oral medicines: The best known ED medications are the Big Three: Viagra (sildenafil citrate, made by Pfizer, Inc.), Levitra (vardenafil HCl, made by Bayer and GlaxoSmithKline), and Cialis (tadalafil, made by Eli Lilly). The three are chemically very similar, and all have proven very effective. Because they are effective, convenient, and relatively inexpensive (about nine dollars per pill), these medicines have become the treatment of choice for most men experiencing ED.