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Erectile Dysfunction Overview

        Health | Sexual Dysfunction

Understanding Erectile Dysfunction

Approximately 22 percent of males between ages 20 and 75 in the United States suffer currently from erectile dysfunction. However, it is estimated that more than 50 percent of men between the ages of 40 and 70 suffer from erectile dysfunction at some time in their lives and about 10 percent of the men in that broad age group suffer complete erectile dysfunction. According to demographic studies and a projection of the U.S. population, the numbers of men with ED are going to increase dramatically. As a result, effective detection and treatment of ED will be an important health care priority. The most effective detection would start at home with the patient, but before symptoms can be diagnosed, the condition must be understood.

50 percent of men between the ages of 40 and 70 suffer from erectile dysfunction.
©2006 Publications International, Ltd.
50 percent of men between the ages of
40 and 70 suffer from
erectile dysfunction.

What Is Erectile Dysfunction?
Now that we have a better understanding of what erectile dysfunction is, let's take a look at some of the causes of the condition in the next section.

Every man has trouble achieving an erection from time to time. Fatigue, anxiety, and excessive alcohol consumption, among other factors, can all cause an occasional problem. Men who experience a sudden inability to have an erection often have a psychological origin to their condition. Just as an erection can result from thinking about sex, negative thoughts, such as those about financial problems, disagreements with a partner, or problems on the job, can prevent men from having an erection or limit its duration. Typically, men with this sort of erectile problem continue to have erections while they sleep or when they get up in the morning.

But an occasional problem achieving an erection is not the same as ED. Erectile dysfunction is the persistent inability to achieve or maintain an erection that is satisfactory for sexual intercourse, according to the National Institutes of Health. This is the accepted medical definition. The persistence of the problem is most significant; ED is chronic.

Why call it erectile dysfunction and not impotence, the word with which the public is most familiar? Because the word impotence is laden with heavy, negative connotations. Erectile dysfunction, on the other hand, simply and accurately describes the physical problem. While men with ED may be unable to have an erection sufficient for penetration, they may very well have a normal sex drive and the ability to achieve orgasm and to ejaculate. Their fertility is not affected.

The Anatomy of an Erection
To understand what causes erectile dysfunction, it is helpful to understand the physiology of the penis and how an erection occurs. The penis contains three chambers. Two chambers, paired on top, are called the corpora cavernosa and run along the length of the organ. One chamber on the bottom is called the corpora spongiosum and contains the urethra, or urinary channel. The chambers are each surrounded by an elastic membrane called the tunica albuginea.

The chambers inside the penis are filled with spongy tissue which, in fact, is smooth muscle similar to the muscle in the bowel and bladder. On cross section, this smooth muscle looks a little like a sliced tomato. The spongy tissue contains smooth muscles, fibrous tissues, veins, arteries, and spaces. When the penis is unaroused and flaccid, the arteries are small, the spaces collapsed, and what little blood goes in is allowed to leave through the veins.

Erection begins with mental and physical stimulation. Impulses from the brain and nerves prompt nerve endings in the penis to release nitric oxide (NO), causing the smooth muscles of the corpora cavernosa to relax, enlarging the tomatolike spaces and allowing blood to flow in and fill them. The blood creates pressure, causing the penis to expand. When the spongy tissue is completely full of blood, an erection occurs. The tunica albuginea traps the blood by compressing the veins, sustaining the erection. The process is reversed when a different set of nerves releases epinephrine, or adrenaline, which causes muscles to contract, minimizing the inflow of blood and opening outflow channels.

Achieving an erection, then, requires a sequence of events. Once initiated, a sexually stimulated erection is maintained by a complex interplay between blood vessels and nerves. The muscles have to relax, the arteries have to dilate, and the veins have to compress -- all at the same time. Should anything disrupt this sequence of events, you may experience erectile dysfunction. This includes disruption in nerve impulses in and between the brain, spinal cord, and penis and damage/malfunction in muscles, fibrous tissues, veins, and arteries in and near the corpora cavernosa.

This information is solely for informational purposes. IT IS NOT INTENDED TO PROVIDE MEDICAL ADVICE. Neither the Editors of Consumer Guide (R), Publications International, Ltd., the author nor publisher take responsibility for any possible consequences from any treatment, procedure, exercise, dietary modification, action or application of medication which results from reading or following the information contained in this information. The publication of this information does not constitute the practice of medicine, and this information does not replace the advice of your physician or other health care provider. Before undertaking any course of treatment, the reader must seek the advice of their physician or other health care provider.