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.
Erectile dysfunction, can be a total inability to achieve erection, an inconsistent ability to do so, or a tendency to sustain only brief erections. These variations make defining Erectile Dysfunction and estimating its incidence difficult. Estimates range from 15 million to 30 million, depending on the definition used. According to the National Ambulatory Medical Care Survey (NAMCS), for every 1,000 men in the United States, 7.7 physician office visits were made for Erectile Dysfunction in 1985. By 1999, that rate had nearly tripled to 22.3. The increase happened gradually, presumably as treatments such as vacuum devices and injectable drugs became more widely available and discussing erectile function became accepted. Perhaps the most publicized advance was the introduction of the oral drug sildenafil citrate (Viagra) in March 1998. NAMCS data on new drugs show an estimated 2.6 million mentions of Viagra at physician office visits in 1999, and one-third of those mentions occurred during visits for a diagnosis other than Erectile Dysfunction.
In older men, Erectile Dysfunction 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 Erectile Dysfunction. Incidence increases with age: About 5 percent of 40-year-old men and between 15 and 25 percent of 65-year-old men experience Erectile Dysfunction. But it is not an inevitable part of aging.
Erectile Dysfunction 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 Erectile Dysfunction. Urologists, who specialize in problems of the urinary tract, have traditionally treated Erectile Dysfunction; however, urologists accounted for only 25 percent of Viagra mentions in 1999.
How does an erection occur?
The penis contains two chambers called the corpora cavernosa, which run the length of the organ (see figure 1). 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 Erectile Dysfunction?
Since an erection requires a precise sequence of events, Erectile Dysfunction can occur when any of the events is disrupted. The sequence includes nerve impulses in the brain, spinal column, and 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 Erectile Dysfunction. Diseases—such as diabetes, kidney disease, chronic alcoholism, multiple sclerosis, atherosclerosis, vascular disease, and neurologic disease—account for about 70 percent of Erectile Dysfunction cases. Between 35 and 50 percent of men with diabetes experience Erectile Dysfunction.
Also, surgery (especially radical prostate and bladder surgery for cancer) can injure nerves and arteries near the penis, causing Erectile Dysfunction. Injury to the penis, spinal cord, prostate, bladder, and pelvis can lead to Erectile Dysfunction by harming nerves, smooth muscles, arteries, and fibrous tissues of the corpora cavernosa.
In addition, many common medicines—blood pressure drugs, antihistamines, antidepressants, tranquilizers, appetite suppressants, and cimetidine (an ulcer drug)—can produce Erectile Dysfunction 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 Erectile Dysfunction cases. Men with a physical cause for Erectile Dysfunction frequently experience the same sort of psychological reactions (stress, anxiety, guilt, depression).
Other possible causes are smoking, which affects blood flow in veins and arteries, and hormonal abnormalities, such as not enough testosterone.
Diagnosis of Erectile Dysfunction
Patient Medical History
Medical and sexual histories help define the degree and nature of Erectile Dysfunction. A medical history can disclose diseases that lead to Erectile Dysfunction, while a simple recounting of sexual activity might distinguish among problems with sexual desire, erection, ejaculation, or orgasm.
Using certain prescription or illegal drugs can suggest a chemical cause, since drug effects account for 25 percent of Erectile Dysfunction cases. Cutting back on or substituting certain medications can often alleviate the problem.
A physical examination can give clues to systemic problems. For example, if the penis is not sensitive to touching, a problem in the nervous system may be the cause. Abnormal secondary sex characteristics, such as hair pattern or breast enlargement, can point to hormonal problems, which would mean that the endocrine system is involved. 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 laboratory tests can help diagnose Erectile Dysfunction. Tests for systemic diseases include blood counts, urinalysis, lipid profile, and measurements of creatinine and liver enzymes. Measuring the amount of free testosterone in the blood can yield information about problems with the endocrine system and is indicated especially in patients with decreased sexual desire.
Monitoring erections that occur during sleep (nocturnal penile tumescence) can help rule out certain psychological causes of Erectile Dysfunction. Healthy men have involuntary erections during sleep. If nocturnal erections do not occur, then Erectile Dysfunction 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.
A psychosocial examination, using an interview and a questionnaire, reveals psychological factors. A man's sexual partner may also be interviewed to determine expectations and perceptions during sexual intercourse.
Treatments of Erectile Dysfunction
Erectile dysfunction, 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.
Psychotherapy and behavior modifications in selected patients are considered next if indicated, followed by oral or locally injected drugs, vacuum devices, and surgically implanted devices. In rare cases, surgery involving veins or arteries may be considered.
Experts often treat psychologically based Erectile Dysfunction 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 Erectile Dysfunction from physical causes is being treated.
Drug Therapy for erectile dysfunction
Drugs for treating Erectile Dysfunction 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 (FDA) approved Viagra, the first pill to treat Erectile Dysfunction. 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.
Research on drugs for treating Erectile Dysfunction is expanding rapidly. Patients should ask their doctor about the latest advances.
Mechanical vacuum devices cause erection by creating a partial vacuum, which draws blood into the penis, engorging and expanding it. The devices have three components: a plastic cylinder, into which the penis is placed; a pump, which draws air out of the cylinder; and an elastic band, which is placed around the base of the penis to maintain the erection after the cylinder is removed and during intercourse by preventing blood from flowing back into the body (see figure 2).
One variation of the vacuum device involves a semirigid rubber sheath that is placed on the penis and remains there after erection is attained and during intercourse.
Surgery usually has one of three goals:
- To implant a device that can cause the penis to become erect
- To reconstruct arteries to increase flow of blood to the penis
- To block off veins that allow blood to leak from the penile tissues
Implanted devices, known as prostheses, can restore erection in many men with Erectile Dysfunction. Possible problems with implants include mechanical breakdown and infection, although mechanical problems have diminished in recent years because of technological advances.
Things to Consider
- Erectile dysfunction (ED) is the inability to get or keep an erection firm enough for complete sexual intercourse.
- Erectile Dysfunction usually has a physical underlaying cause.
- Erectile Dysfunction is treatable no matter what age.
- Erectile Dysfunction affects up to 30 million American men.
- Treatments for Erectile Dysfunction include: psychotherapy, drug therapy, vacuum devices, and surgery.