Erectile Dysfunction - causes, symptoms and treatment
What is Erectile Dysfunction
Erectile Dysfunction - The reduced ability or inability for a man’s PENIS to become erect or sustain an erection adequate for SEXUAL INTERCOURSE. Erectile dysfunction, sometimes called impotence, may occur as a physiologic condition, psychologic or emotional condition, or combination. Most commonly, however, all of these factors contribute to the condition. About 25 million men in the United States have chronic (long-term) erectile dysfunction.
Causes of Erectile Dysfunction
Physiologic causes of erectile dysfunction include
- NERVE damage that occurs as a complication of PROSTATECTOMY (surgery to remove the PROSTATE GLAND)
- DIABETES, which progressively damages the body’s arteries and nerves
- peripheral NEUROPATHY, which may damage the nerves that supply the penis
- MULTIPLE SCLEROSIS, a degenerative neurologic disorder that causes loss of nerve function in various areas of the body
- ATHEROSCLEROSIS, which may occlude the arteries that serve the penis and slow the flow of BLOOD to the penis
- chronic LIVER disease or chronic kidney disease
- SPINAL CORD INJURY or TRAUMATIC BRAIN INJURY (TBI), either of which may interrupt the flow of nerve impulses between the CENTRAL NERVOUS SYSTEM and the PERIPHERAL NERVOUS SYSTEM
Cigarette smoking is a key contributing factor for neuropathy and atherosclerosis, compounding the effect these conditions have throughout the body. Numerous medications may cause erectile dysfunction as an undesired SIDE EFFECT. The most common culprits are ANTIDEPRESSANT MEDICATIONS, antihypertensive medications to treat HYPERTENSION (high BLOOD PRESSURE), and ANTIHISTAMINE MEDICATIONS to treat seasonal allergies. Fear, stress, anxiety, and DEPRESSION are among the psychologic and emotional causes of erectile dysfunction.
ERECTILE DYSFUNCTION AND HEART DISEASE
Studies suggest erectile dysfunction in otherwise healthy men is a harbinger of HEART disease, notably ATHEROSCLEROSIS and CORONARY ARTERY DISEASE (CAD). The small arteries that flood the PENIS with BLOOD during ERECTION appear to show the effects of accumulated arterial plaque earlier than other arteries in the body. Though other arteries of similar size likely occlude to similar extent, men are more likely to notice and pay attention to circumstances that interfere with erection.
Symptoms of Erectile Dysfunction and Diagnostic Path
The inability to get or sustain an adequate erection is the symptom of erectile dysfunction. The diagnostic path begins with a thorough physical examination, including DIGITAL RECTAL EXAMINATION (DRE) to assess the status of the prostate gland and blood tests to measure the levels of lipids (cholesterol and triglycerides), TESTOSTERONE, GLUCOSE (fasting blood glucose), and liver enzymes. The doctor may desire additional diagnostic procedures, depending on the results of these preliminary tests. Such procedures may include Doppler ULTRASOUND to assess the flow of blood to and within the penis, testing of nerve function and reflexes, and other factors of function. Because a man normally experiences multiple erections during sleep, some tests are done when the man is sleeping (such as the nocturnal penile tumescence test), to measure the characteristics of nocturnal erections.
Erectile Dysfunction Treatment Options and Outlook
Treatment targets the underlying cause when it is identifiable. About 85 percent of erectile dysfunction results from physiologic causes. Sometimes treatment is straightforward and relatively easy, such as changing to a different medication when the cause of erectile dysfunction is medication side effect. Often, however, the most effective treatment addresses multiple contributing factors and encompasses medical interventions, lifestyle modifications, and psychologic therapy or counseling.
Medical interventions
Phosphodiesterase (PDE) inhibitors, also called selective enzyme inhibitors, are the least intrusive and often most successful medical treatment for erectile dysfunction. The best known of these oral medications to treat erectile dysfunction is sildenafil, first marketed under the trade name Viagra. Other medications in this classification include vardenafil (Levitra) and tadalafil (Cialis). These drugs work by delaying the enzyme-initiated process through which an erection subsides, extending the erection. The erection still requires sexual stimulation to develop; these medications do not cause spontaneous erection. Men who take certain medications to treat HEART disease, such as some antihypertensive medications to treat high blood pressure, cannot take PDE inhibitors because the actions of the drugs are similar and combining them can cause fatally low blood pressure. PDE inhibitors are most effective in men who have mild to moderate vascular disease (such as atherosclerosis) or arterial damage due to diabetes.
Prescription-strength preparations of the herbderived product YOHIMBE/YOHIMBINE also may extend erections though work through a different mechanism. Yohimbe (the herb) and yohimbine (the active ingredient derived from the herb) products require a doctor’s prescription in the United States because they act on the parasympathetic NERVOUS SYSTEM (a division of the autonomic nervous system that regulates certain involuntary functions). Yohimbe/yohimbine products are most effective in men who have mild to moderate neuropathy (nerve damage). The supplement arginine may also decrease erectile dysfunction by increasing nitric oxide.
Other medications that cause erection are selfinjected into the penis or inserted as tiny suppositories (about the size of a grain of rice) into the urethral meatus (opening of the URETHRA at the tip of the penis). These medications contain alprostadil, a formulation of PROSTAGLANDINS, that instigates the sequence of events within the penis that cause it to engorge and stiffen. Unlike oral PDE inhibitors, these medications do cause erection regardless of sexual stimulation because they act directly on the smooth MUSCLE within the penis that causes the corpora cavernosa to relax and fill with blood. The primary drawback to these medications is their form of administration, which limits their appeal as well as the frequency with which a man may use them (no more often than once every five days).
Surgery to repair damaged blood vessels or insert penile implants is an option for erectile dysfunction that does not respond to medications.The most commonly used penile implants are a combination of inflatable tubes, a tiny pump, and small reservoirs that contain a sterile fluid. The man activates the pump, usually placed in the SCROTUM or at the base of the penis, to fill the tubes to acquire an erection. A valve releases the fluid back into the reservoir.
Lifestyle modifications
Lifestyle modifications such as weight loss, daily physical exercise, SMOKING CESSATION, and reduced ALCOHOL consumption can improve circulation and nerve function. Exercise in particular also helps reduce stress.
Psychologic therapy
Counseling or sex therapy may be helpful when there are emotional factors at play. These factors may cause erectile dysfunction or develop because of it and then perpetuate it. Therapy may be individual or involve the sexual partner.
Erectile Dysfunction - Risk Factors and Preventive Measures
Erectile dysfunction becomes more common after age 50. The key health risks for erectile dysfunction are cigarette smoking, OBESITY, diabetes, longterm ALCOHOLISM, CARDIOVASCULAR DISEASE (CVD), prostate disease, and kidney disease. Lifestyle significantly influences these factors. Lifestyle measures to reduce these risks include smoking cessation, nutritious EATING HABITS, daily physical exercise, moderation in or cessation of alcohol consumption, and weight management. Medical measures include management of blood lipid levels (cholesterol and triglycerides) and diligent control of blood glucose and INSULIN levels in men who have diabetes through appropriate medication therapy.
See also AGING, REPRODUCTIVE AND SEXUAL CHANGES THAT OCCUR WITH; BENIGN PROSTATIC HYPERPLASIA (BPH); DIET AND HEALTH; EXERCISE AND HEALTH; GENERAL ANXIETY DISORDER (GAD); PRIAPISM; PROSTATE HEALTH; SEXUAL HEALTH; WEIGHT LOSS AND WEIGHT MANAGEMENT.
