Impotence / Erectile Dysfunction

What is erectile dysfunction (ED)?

Impotence, or erectile dysfunction (ED), 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), 15 million 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 80 percent to 90 percent of impotence 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 erectile dysfunction?

According to the American Urological Association, 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 (5 percent or less), 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 causes of ED?

According to the National Institutes of Health (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 persons with diabetes. There are 8.7 million adult men in the US with diabetes, and it is estimated that 35 percent to 50 percent are impotent. The process involves premature and unusually severe hardening of the arteries. Peripheral neuropathy, with involvement of the nerves controlling erections, is commonly seen in persons 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, anti-anxiety 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 body-builders, 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.

Treatment for ED:

Specific treatment for ED will be determined by your physician 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

Some of the treatments available for ED include the following:

medical treatments
- sildenafil citrate (Viagra™)
  Viagra is 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 prostetectomy.
- 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 and may last up to 36 hours.
The US Food and Drug Administration (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 physician 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 retina 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. Elderly 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 form and as a skin patch.
penile implants
There are three types of implants used to treat ED, including the following:
- hydraulic pump - a pump and two cylinders are placed within the erection chambers of the penis which 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 which allows manipulation into an erect or non-erect 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.

Coping 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.

Feeling embarrassed about being impotent may prevent many men from seeking the medical attention they need, which can delay diagnosis and treatment for more serious underlying conditions. Impotence itself is often related to an underlying problem, such as heart disease, diabetes, liver disease, or other medical conditions.

Since impotence can be a forewarning symptom of progressive coronary disease, physicians should be more direct when questioning patients about their health. By asking patients more directly about their sexual function, through conversation or a questionnaire during a check-up, physicians may be able to detect more serious health conditions sooner.

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