Erectile dysfunction (ED), sometimes referred to by its old name, impotence, refers to a condition where a man has difficulty obtaining and/or maintaining an erection sufficient for sexual intercourse. It can range from occasional difficulty keeping a firm erection to the total inability to obtain any erection at all. The best estimates suggest that between 15 million and 30 million men in the United States currently suffer from ED.
In order for a man to have an erection, he must possess well-functioning neurologic, vascular, and hormonal systems. Running the length of the penis are two chambers, called the corpora cavernosas. When a man becomes sexually excited due to physical or psychological stimulation, impulses from the brain and local nerves signal muscles in the corpora cavernosa to relax, thereby allowing extra blood into these chambers. As a result, the penis becomes more rigid, allowing for vaginal penetration. This process also requires appropriate levels of certain hormones, particularly testosterone. Any medical condition (e.g., diabetes, prostate surgery) or drug (antidepressants, antihypertensives) that interferes with the hormones, nerve conduction, or blood flow necessary for an erection can result in ED.
The prevalence of ED increases with age, from less than 20% at age 40 to approximately 35% (or more) at age 65. This increase is largely the result of the greater frequency of age-associated medical conditions that can impact sexual functioning, as well as the larger number of medications taken by older men that can interfere with erections. Yet getting older does not necessarily lead to the development of ED. Many men are sexually potent well into their 70s and even beyond.
In addition to medical causes for ED, psychological factors can also interfere with sexual functioning. For example, when a man is depressed or anxious, the body’s ability to direct blood-flow to the penis can be compromised.
Fortunately, there are several effective treatments for ED. The most popular are the oral medications (Viagra, Cialis, Levitra) that cause the smooth muscles of the penis to relax, enabling blood to flow into the penis. These drugs, while highly effective, do not work for everyone. Other medical treatments include penile injections of vasodilators, urethral suppositories, vacuum devices, and penile implants. While effective, all of these medical treatments have side effects (sometimes quite serious ones) associated with them. When ED is primarily the result of psychological factors (e.g., stress), psychotherapy alone may be sufficient to remedy the problem.
References:
- Jones, S. (2003). Overcoming impotence: A leading urologist tells you everything you need to know. Amherst, NY: Prometheus Books.
- Parker, J. N. (2002). The 2002 official patient’s sourcebook on impotence. San Diego, CA: Icon
- WebMD, , http://webmd.com (search Impotence; ErectileDysfunction)