Erectile Dysfunction Overview
Erectile dysfunction, also called impotence, is the inability to attain or maintain an erection of the penis that is firm enough for penetration during sexual intercourse. To initiate and maintain an erection, the penis must fill with blood. Nerve signals stimulate this engorgement. They prompt the blood vessels in the penis to expand so blood can fill it. Meanwhile, other blood vessels constrict, trapping blood inside.
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The following factors can cause erectile dysfunction:
Venous Leak:If the blood vessels (veins), which normally are compressed by the blood filling the penis during an erection, are not fully compressed, an erection may not be attainable, or may not last long. This can be caused by injury or diseases which prevent the full expansion of the vessels (arteries) which normally expand with blood.
Neurovascular Function:Erection cannot be attained if nerve signals do not prompt blood vessels to do their job or if blood flow to the penis is reduced. Nerve dysfunction can also diminish feeling in the penis, resulting in impotence. Many medications can cause erectile dysfunction by impairing either vascular or nerve function.
Medical conditions that can lead to neurovascular dysfunction include:
- Diabetes —can interfere with nerve signals
- Arteriosclerosis (hardening of the arteries)—can reduce blood flow
- Peripheral neuropathy , spinal cord injury, and surgery—can affect nerve function
Psychological Factors:Psychological factors account for 10%-15% of erectile dysfunction cases. The brain initiates many of the nerve signals required for a successful erection. Problems in your relationship, feelings of guilt associated with sex, depression , anxiety , and stress can all lead to erectile dysfunction
An estimated 25-30 million US men have erectile dysfunction. Erectile dysfunction increases with age, affecting about 20% of men aged 20 and older and 78% of men aged 75 and older.
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DynaMed editorial team. Erectile dysfunction. EBSCO DynaMed website. Available at:
. Updated August 2, 2010. Accessed August 10, 2010.
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National Library of Medicine website. Available at:
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