Erectile Dysfunction and Treatment

Overview

Erectile dysfunction, sometimes called "impotence," is the repeated inability to get or keep an erection firm enough for sexual intercourse. The word "impotence" may also be used to describe other problems that interfere with sexual intercourse and reproduction, such as lack of sexual desire and problems with ejaculation or orgasm. Using the term "erectile dysfunction" makes it clear that those other problems are not involved.

Symptoms

Erectile dysfunction, or ED, can be a total inability to achieve erection, or an inconsistent ability to do so, or a tendency to sustain only brief erections. These variations make defining ED and estimating its incidence difficult. Estimates range from 15 million to 30 million men, depending on the definition used.
ED is treatable at any age, and awareness of this fact has been growing. More men have been seeking help and returning to normal sexual activity because of improved, successful treatments for ED. Urologists, who specialize in problems of the urinary tract, have traditionally treated ED; however, urologists accounted for only 25 percent of Viagra prescriptions in 1999.

In older men, ED usually has a physical cause, such as disease, injury or side effects of drugs. Any disorder that causes injury to the nerves or impairs blood flow in the penis has the potential to cause ED.

How Does an Erection Occur?

The penis contains two chambers, called the corpora cavernosa, which run the length of the penis. A spongy tissue fills the chambers. The corpora cavernosa are surrounded by a membrane, called the tunica albuginea. The spongy tissue contains smooth muscles, fibrous tissues, spaces, veins and arteries. The urethra, which is the channel for urine and ejaculate, runs along the underside of the corpora cavernosa and is surrounded by the corpus spongiosum.

Erection begins with sensory or mental stimulation, or both. Impulses from the brain and local nerves cause the muscles of the corpora cavernosa to relax, allowing blood to flow in and fill the spaces. The blood creates pressure in the corpora cavernosa, making the penis expand. The tunica albuginea helps trap the blood in the corpora cavernosa, thereby sustaining erection. When muscles in the penis contract to stop the inflow of blood and open outflow channels, erection is reversed.

What Causes ED?

Since an erection requires a precise sequence of events, ED can occur when any of these events is disrupted. The sequence includes nerve impulses in the brain, spinal column and the area around the penis, and response in muscles, fibrous tissues, veins and arteries in and near the corpora cavernosa.
Damage to nerves, arteries, smooth muscles and fibrous tissues, often as a result of disease, is the most common cause of ED. Diseases--such as diabetes, kidney disease, chronic alcoholism, multiple sclerosis, atherosclerosis, vascular disease and neurologic disease--account for about 70 percent of ED cases.

Surgery (especially radical prostate and bladder surgery for cancer) can injure nerves and arteries near the penis, causing ED. Injury to the penis, spinal cord, prostate, bladder and pelvis can lead to ED by harming nerves, smooth muscles, arteries and fibrous tissues of the corpora cavernosa.

Many common medications--blood pressure drugs, antihistamines, antidepressants, tranquilizers, appetite suppressants and cimetidine (an ulcer drug)--can produce ED as a side effect.

Experts believe that psychological factors such as stress, anxiety, guilt, depression, low self-esteem and fear of sexual failure cause 10 to 20 percent of ED cases. Men with a physical cause for ED frequently experience the same sort of psychological reactions (stress, anxiety, guilt or depression).

How is ED Diagnosed?

Physical Examination

A physical examination can give clues to systemic problems. The examiner might discover a circulatory problem by observing decreased pulses in the wrist or ankles. And unusual characteristics of the penis itself could suggest the source of the problem--for example, a penis that bends or curves when erect could be the result of Peyronie's disease.

Several blood tests can help diagnose ED. Other Tests may include: monitoring erections that occur during sleep (nocturnal penile tumescence) can help rule out certain psychological causes of ED. Healthy men have involuntary erections during sleep. If nocturnal erections do not occur, then ED is likely to have a physical rather than psychological cause. Tests of nocturnal erections are not completely reliable, however. Scientists have not standardized such tests and have not determined when they should be applied for best results.

Treatment

Most physicians suggest that treatments proceed from least to most invasive. Cutting back on any drugs with harmful side effects is considered first. For example, drugs for high blood pressure work in different ways. If you think a particular drug is causing problems with erection, tell your doctor and ask whether you can try a different class of blood pressure medicine or a different antidepressant.

Psychotherapy and behavior modifications in selected patients are considered next if indicated, followed by oral or locally injected drugs. In rare cases, surgery involving veins or arteries may be considered.

Psychotherapy

Experts often treat psychologically based ED using techniques that decrease the anxiety associated with intercourse. The patient's partner can help with the techniques, which include gradual development of intimacy and stimulation. Such techniques also can help relieve anxiety when ED from physical causes is being treated.

Drug Therapy

Drugs for treating ED can be taken orally, injected directly into the penis or inserted into the urethra at the tip of the penis. In March 1998, the Food and Drug Administration approved Viagra, the first pill to treat ED. In August 2003, the FDA gave approval to a second oral medicine, vardenafil hydrochloride (Levitra). Additional oral medicines are being tested for safety and effectiveness.

Taken an hour before sexual activity, Viagra and Levitra work by enhancing the effects of nitric oxide, a chemical that relaxes smooth muscles in the penis during sexual stimulation and allows increased blood flow.
Neither Viagra nor Levitra should be used more than once a day. Men who take nitrate-based drugs such as nitroglycerin for heart problems should not use either drug because the combination can cause a sudden drop in blood pressure. Also, Levitra should not be taken with any of the drugs called alpha-blockers, which are used to treat prostate enlargement or high blood pressure. Many men achieve stronger erections by injecting prescription drugs into the penis, causing it to become engorged with blood. These drugs may create unwanted side effects, however, including persistent erection (known as priapism) and scarring. Nitroglycerin, a muscle relaxant, can sometimes enhance erection when rubbed on the penis.

Since research on drugs for treating ED is expanding rapidly. Patients should ask their doctor about the latest advances.

Advances in suppositories, injectable medications, implants and vacuum devices have expanded the options for men seeking treatment for ED. These advances have also helped increase the number of men seeking treatment. Gene therapy for ED is now being tested in several centers and may offer a long-lasting therapeutic approach for ED.

Points to Remember

Erectile dysfunction (ED) is the repeated inability to get or keep an erection firm enough for sexual intercourse.
ED affects 15 to 30 million American men.
ED usually has a physical cause.
ED is treatable at all ages.
Treatments include psychotherapy, drug therapy, vacuum devices and surgery.