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Erectile Dysfunction (ED)/Impotence

What is ED?

Impotence, or erectile dysfunction, may result from the total inability to achieve erection, an inconsistent ability to achieve an erection, or the ability to only sustain a brief erection. According to the National Institutes of Health (NIH), up to 30 million men are affected by ED, depending on the definition used.

Although in the past it was commonly believed to be due to psychological problems, it is now known that for most men erectile dysfunction is caused by physical problems, usually related to the blood supply of the penis. Many advances have occurred in both diagnosis and treatment of ED.

What are the risk factors for ED?

One risk factor is advancing age. According to the American Urological Association (AUA), as men age, the level of circulating testosterone decreases, which may interfere with normal erection. While a low testosterone level itself is rarely the cause of ED, low testosterone can be an additional contributing factor in many men who have other risk factors for ED. Other risk factors for ED include various medical problems, such as hypertension (abnormally high blood pressure), diabetes, vascular disease, and high levels of blood cholesterol. Smoking and drug and alcohol abuse also are risk factors for ED. 

What are the the causes of ED?

According to the NIH, ED also is a symptom in many disorders and diseases. Causes of ED include the following:

  • Premature ejaculation (PE). Premature ejaculation is the inability to maintain an erection long enough for mutual satisfaction. Premature ejaculation is divided into primary and secondary forms. Primary premature ejaculation is a learned behavior that begins when a male first becomes sexually active (as opposed to organic or physical) impotence. Secondary premature ejaculation occurs when, after years of normal ejaculation, the duration of intercourse grows progressively shorter. Secondary PE is due to physical causes, usually involving the penile arteries, veins, or both.

  • Performance anxiety. Performance anxiety is a form of psychological impotence, usually caused by stress or anxiety.

  • Depression. Depression is another cause of psychological impotence. Some antidepressant medications cause erectile failure.

  • Organic impotence. Organic impotence involves the penile arteries, veins, or both, and is the most common cause of impotence, especially in older men. When the problem is arterial, it is usually caused by arteriosclerosis, or hardening of the arteries, although trauma to the arteries may be the cause. The controllable risk factors for arteriosclerosis--being overweight, lack of exercise, high cholesterol, high blood pressure, and cigarette smoking--can cause erectile failure often before progressing to affect the heart. Many experts believe that when veins are the cause, a venous leak or cavernosal failure is the most common vascular problem.

  • Venous leak. Venous leak may be caused when the veins in the penis cannot prevent blood from leaving the penis during erection. This may be congenital or result from damage to the veins of the penis.

  • Diabetes. Impotence is common in people with diabetes. The process involves premature and unusually severe hardening of the arteries. Peripheral neuropathy, with involvement of the nerves controlling erections, is commonly seen in people with diabetes.

  • Neurologic causes. There are many neurological (nerve problems) causes of impotence. Diabetes, chronic alcoholism, multiple sclerosis, heavy metal poisoning, spinal cord and nerve injuries, and nerve damage from pelvic operations can cause ED.

  • Drug-induced impotence. A great variety of prescription drugs, such as blood pressure medications, antianxiety and antidepressant medications, glaucoma eye drops, and cancer chemotherapy agents are just some of the many medications associated with impotence.

  • Hormone-induced impotence. Hormonal abnormalities, such as increased prolactin (a hormone produced by the anterior pituitary gland), steroid abuse by bodybuilders, too much or too little thyroid hormone, and hormones administered for prostate cancer may cause impotence. Rarely is low testosterone responsible for impotence.

  • Peyronie's disease. Peyronie's disease is a rare inflammatory condition that causes scarring of erectile tissue that may result in curvature of the penis. This condition can impair sexual function.

How is ED diagnosed?

The AUA states that for most men, a diagnosis will require a simple medical history, physical examination, and a few routine blood tests. Most patients do not require extensive testing before beginning treatment. 

Diagnostic procedures for ED may include the following:

  • Patient medical/sexual history. This may reveal conditions or diseases that lead to impotence and help distinguish among problems with erection, ejaculation, orgasm, or sexual desire.

  • Physical examination. This is done to look for evidence of systemic problems, such as the following:

    • A problem in the nervous system may be involved if the penis does not respond as expected to certain touching.

    • Secondary sex characteristics, such as hair pattern, can point to hormonal problems, which involve the endocrine system.

    • Circulatory problems could be indicated by an aneurysm.

    • Unusual characteristics of the penis itself could suggest the basis of the impotence.

  • Lab tests. These are done to help diagnose impotence and include blood counts, urinalysis, lipid profile, and measurements of creatinine and liver enzymes. When low sexual desire is a symptom, measurement of testosterone in the blood can yield information about problems with the endocrine system.

  • Psychosocial examination. This is done to help reveal psychological factors that may be affecting performance. The sexual partner also may be interviewed to determine expectations and perceptions encountered during sexual intercourse.

What is the treatment for ED?

Specific treatment for erectile dysfunction will be determined by your doctor based on:

  • Your age, overall health, and medical history

  • Extent of the disease

  • Your tolerance for specific medications, procedures, or therapies

  • Expectations for the course of the disease

  • Your opinion or preference

Below are some of the treatments available for ED.

Medical treatments

These are the common medications used to treat ED:

  • Sildenafil citrate (Viagra). A prescription medication taken orally for the treatment of ED. Viagra does not directly cause penile erection, but affects the response to sexual stimulation.

  • Vardenafil citrate (Levitra). In clinical studies, Levitra has been shown to work quickly and improve sexual function in men the first time they take the medication. It has been shown to work well in men of all ages, in men with diabetes, and in men who have had the surgical procedure called radical prostatectomy.

  • Tadalafil citrate (Cialis). Studies have indicated that Cialis stays in the body longer than other medications in its class. Most men who take this medication find that an erection occurs within 30 minutes and the effects of the medication may last up to 36 hours.

The FDA recommends that men follow general precautions before taking a medication for ED. Men who are taking medications that contain nitrates, such as nitroglycerin, should NOT use Viagra, Levitra, or Cialis. Taking nitrates with one of these medications can lower blood pressure too much. In addition, men who take Levitra or Cialis should not use alpha blockers, as they could result in hypotension (abnormally low blood pressure). Experts recommend that men have a complete medical history and physical examination to determine the cause of ED. Men should tell their doctor about all the medications they are taking, including over-the-counter medications.

In addition, men should not take these medications if they have a history of heart attack or stroke, or if they have a bleeding disorder or stomach ulcers.

Men with medical conditions that may cause a sustained erection, such as sickle cell anemia, leukemia, or multiple myeloma, or a man who has an abnormally-shaped penis, may not be able to benefit from these medications. Also, men with liver diseases or a disease of the retina, such as macular degeneration or retinitis pigmentosa, may not be able to take these medications, or may need to take the lowest dosage.

These medical treatments should NOT be used by women or children. Older men are especially sensitive to the effects of these medical treatments, which may increase their chance of having side effects.

Hormone replacement therapy

Testosterone replacement therapy may improve energy, mood, and bone density, increase muscle mass and weight, and heighten sexual interest in older men who may have deficient levels of testosterone. Testosterone supplementation is not recommended for men who have normal testosterone levels for their age group due to the risk of prostate enlargement and other side effects. Testosterone replacement therapy is available in an oral and injectable form, cream or gel, and as a skin patch. 

Penile implants

Three types of implants are used to treat ED:

  • Hydraulic pump. A pump and two cylinders are placed within the erection chambers of the penis. This causes an erection by releasing a saline solution; it can also remove the solution to deflate the penis.

  • Prosthesis. Two semi-rigid but bendable rods are placed within the erection chambers of the penis. This allows manipulation into an erect or nonerect position.

  • Interlocking soft plastic blocks. These are placed within the erection chambers of the penis and can be inflated or deflated using a cable that passes through them. 

Infection is the most common cause of penile implant failure and is treatable with antibiotics. In some cases, the infected implant must be replaced by a new implant. Implants are usually not considered until other methods of treatment have been tried. 

How do couples cope with ED?

Erectile dysfunction can cause strain on a couple. Many times, men will avoid sexual situations due to their emotional pain associated with ED, causing their partner to feel rejected or inadequate. It is important to communicate openly with your partner. Some couples consider seeking treatment for ED together, while other men prefer to seek treatment without their partner's knowledge. A lack of communication is the primary barrier for seeking treatment, and can prolong the suffering. The loss of erectile capacity can have a profound effect on a man. The good news is that ED can usually be treated safely and effectively.