3 Top Causes of Erectile Dysfunction


Erectile dysfunction, or the inability to get and keep an erection, has a variety of causes, including nerve disorders, vascular problems, and medications. Here’s what you need to know.

1. Nerve disorders

The nerves are signal carriers that relay information from the brain to the penile tissues. Duly alerted, the blood vessels open, allowing enough blood to rush into the penis to make it rigid. If there is a problem with these nerves, however, either from prostate treatment (surgery or radiation therapy) or diseases that affect the nerves, the messages aren’t transmitted correctly. The outcome is an impaired erection or none at all.

One major cause of penile nerve problems is diabetes, a chronic disorder usually caused by an impaired utilization of insulin, the hormonal substance manufactured by special cells in the pancreas. It is now estimated that 35 percent to 75 percent of men with diabetes suffer from erectile dysfunction. More than half of men with diabetes experience the onset of erectile dysfunction within 10 years of developing the disease.

Having a genetic predisposition and being obese are the most significant factors for diabetes. Diabetes adversely affects the nerves, making it progressively more difficult for nerve impulses to reach the penis. In some cases, diabetes delivers a double threat: in addition to damaging nerves, it can also encourage atherosclerosis in the blood vessels, causing them to become blocked and interrupt blood flow to the penis.

Another situation in which delicate nerves can be damaged, causing erection problems, is when surgery is performed to remove cancer from the lower rectum or colon, or when any radiation therapy is delivered to the pelvic area. Multiple sclerosis (a progressive nervous system disorder) and Parkinson’s disease (a degenerative brain syndrome) also create neurological disturbances that can result in erectile dysfunction. Other nerve disruptions can be triggered by back surgery or by disc herniation in the lower back.

2. Vascular problems

The major cause of vascular erectile difficulties typically originates from problems with the two deep cavernosal arteries, or the larger arteries that feed blood to these cavernosal vessels.

A man experiencing vascular problems may find that his erections become less firm than they once were. He’ll start out with a strong erection, but during the course of sexual activity it will begin to lose rigidity. Over time, he may begin to experience difficulty in having an erection at all.

The culprit is most often atherosclerotic narrowing, which diminishes blood flow through the arteries. This arterial narrowing, which begins when men are in their 20s, is mostly due to a high-fat diet, genetic predisposition, high blood cholesterol, or a combination of all three factors. As the blockage slowly progresses over the years, the arteries are unable to dilate enough to permit increased blood flow to the penis.

3. Medications

In many cases, erectile dysfunction is a side effect of a prescription drug. Currently, more than 200 medications can seriously compromise erections and sexual performance. The most common offenders are medications for high blood pressure, heart ailments, and allergies. Medications used to combat depression— especially the serotonin reuptake inhibitors (SSRIs), such as Prozac, Zoloft, and Paxil — can be a culprit.

Frequently, if a man is taking more than one medication — one for hypertension and another for depression, for example — the damaging effects are cumulative and can result in a complete loss of erectile function.

Other issues

Androgens (testosterone) enhance but are not essential for erections. Up to 20 percent of older men who have castrate levels of testosterone after treatment for prostate cancer can still maintain erections. Low testosterone levels may dampen libido (desire for sexual activity).

Although testosterone supplementation for men with low hormone levels may increase their sexual urge, it almost never increases the ability to have an erection.


Nicotine, a key chemical ingredient in cigarettes, decreases arterial flow and blocks smooth muscle relaxation in penile tissues.

Finally, there is the outdated belief that psychological problems are the fundamental cause of erectile dysfunction. While there are men who do have serious psychological components to their erectile dysfunction, most of these men also have a physiological cause. The psychological part is often a response to their erectile dysfunction, manifested as depression or anxiety. It is rarely the case that psychological problems are the sole cause of erectile dysfunction.

This article originally appeared in Health After 50.