What's Really Causing Your Erection Problems?

Erection problems (erectile dysfunction) may be caused by physical problems related to the blood vessels, nerves, and hormones or by psychological issues. Current evidence suggests that physical causes account for about 80 percent of erection problems.

Normally, an erection occurs when your imagination or senses (vision, hearing, touch, smell, taste) are stimulated and you become aroused. Your central nervous system sends nerve impulses that increase blood flow to your penis. Blood fills the spongy chambers (corpora cavernous) in the penis, causing them to expand and become rigid.

Four requirements for a normal erection are:

A properly functioning nervous system that sends the necessary signals to the penis.

An intact system of blood vessels (vascular system) to allow blood to flow into and out of the penis.

Normal smooth muscle in the penis, which must relax so the penis can fill with blood and enlarge.

The ability to trap the blood in the penis so that it stays firm.

Physical causes of erection problems include long-term (chronic) and short-term (acute) injuries and complications of prostate or other surgery that interfere with nerve impulses or blood flow to the penis. Physical problems are often the cause of erection difficulties in men age 50 or older.

Problems with the blood vessels (vascular problems) may prevent blood from filling the penis or from remaining there long enough to maintain an erection. For example, long-term high blood pressure can cause damage to blood vessels and lead to erection problems.

Problems with the nerves (neurologic problems) may prevent arousal signals from traveling from the brain and spinal cord to the penis. Nerve disorders such as Parkinson's disease, Alzheimer's disease, multiple sclerosis, and stroke may interfere with a man's ability to have an erection and may lower sexual desire. Nerve damage from diabetes, complications from surgery, and spinal cord injury also may cause problems.

Problems with the structure of the penis or its surrounding tissues may prevent an erection.

Hormonal factors, such as a low level of the hormone testosterone, may be involved in causing erection problems.

Side effects of medications (for example, some of those taken for high blood pressure or depression) may include erection problems. In some cases it may be possible to change the dose of the medicine or to use another medicine.

The use of tobacco, alcohol, or illegal drugs can lead to erection problems. Stopping or reducing the use of these substances may reduce the severity of a man's erection problem.

Sleep disorders may also play a role. According to a recent study published in The Journal of Sexual Medicine, men considered at high risk of developing obstructive sleep apnea are more likely to be diagnosed with erectile dysfunction.

Activities that restrict blood flow to the penis also may result in erection problems. Some doctors have observed that men who regularly ride bicycles over long distances are more likely to have erection problems than men who ride only occasionally, especially if they ride on a narrow, unpadded saddle. But the possible link between bicycle riding and erection problems has not been proven.

A vasectomy usually does not cause an erection problem. But pain after the operation may affect sexual performance for a time, and if a man was not comfortable with his decision to have a vasectomy, or is having second thoughts, it could affect him psychologically.

Psychological causes of erection problems include depression (which also has a physical component), anxiety, stress, grief, or problems with current or past relationships. These interfere with the erection process by distracting the man from things that would normally arouse him. Erection problems in men younger than 40 who have no physical risk factors are more likely to be caused by psychological factors than physical causes.

Relationship problems can lead to erection problems. This may happen when a man has been widowed or loses sexual interest in a particular partner.

Some men develop erection problems when they contemplate marriage.

Some men may have difficulty having sexual intercourse with their partner after their first child is born.