Erectile Dysfunction
(Impotence, ED)

1. Take the Impotence (ED) Quiz
2. Impotence Slideshow Pictures
3. Sex Drive Killers Slideshow Pictures

Medical Author:

Dennis Lee, MD

Dennis Lee, MD

Dr. Lee was born in Shanghai, China, and received his college and medical training in the United States. He is fluent in English and three Chinese dialects. He graduated with chemistry departmental honors from Harvey Mudd College. He was appointed president of AOA society at UCLA School of Medicine. He underwent internal medicine residency and gastroenterology fellowship training at Cedars Sinai Medical Center.

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Medical Author:

Siamak T. Nabili, MD, MPH

Siamak T. Nabili, MD, MPH

Dr. Nabili received his undergraduate degree from the University of California, San Diego (UCSD), majoring in chemistry and biochemistry. He then completed his graduate degree at the University of California, Los Angeles (UCLA). His graduate training included a specialized fellowship in public health where his research focused on environmental health and health-care delivery and management.

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Medical Editor:

Jay W. Marks, MD

Jay W. Marks, MD

Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.

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Medical Editor:

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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Erectile dysfunction (ED), also known as impotence, is the inability to achieve or sustain an erection for satisfactory sexual activity. Erectile dysfunction is different from other conditions that interfere with male sexual intercourse, such as lack of sexual desire (decreased libido) and problems with ejaculation and orgasm (ejaculatory dysfunction). This article focuses on the evaluation and treatment of erectile dysfunction.

Erectile dysfunction (ED, impotence) varies in severity; some men have a total inability to achieve an erection, others have an inconsistent ability to achieve an erection, and still others can sustain only brief erections. The variations in severity of erectile dysfunction make estimating its frequency difficult. Many men also are reluctant to discuss erectile dysfunction with their doctors due to embarrassment, and thus the condition is underdiagnosed. Nevertheless, experts have estimated that erectile dysfunction affects 30 million men in the United States.

While erectile dysfunction can occur at any age, it is uncommon among young men and more common in the elderly. By age 45, most men have experienced erectile dysfunction at least some of the time. According to the Massachusetts Male Aging Study, complete impotence increases from 5% among men 40 years of age to 15% among men 70 years and older. Population studies conducted in the Netherlands found that some degree of erectile dysfunction occurred in 20% of men between ages 50-54, and in 50% of men between ages 70-78. In 1999, the National Ambulatory Medical Care Survey counted 1,520,000 doctor-office visits for erectile dysfunction. Other studies have noted that approximately 35% of men 40-70 years of age suffer from moderate to severe ED, and an additional 15% may have milder forms.