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More InDepth Information on This Condition

Impotence is the inability to attain or maintain an erection of the penis that is firm enough for sexual intercourse.

To initiate and maintain an erection, the penis must fill with blood. One type of blood vessels open wide to allow blood into the penis. Meanwhile, a second type of blood vessel squeezes down to keep the blood from leaving the penis. Nerve signals cause the proper changes in the blood vessels.

The following factors can cause erectile dysfunction:

Venous Leak
The blood vessels that keep the blood from leaving the penis may be injured or have disease. This can cause a leak in these vessels. Blood can escape through these leaks during an erection. This means that an erection cannot be made or may not last long.

Neurovascular Function
Problems with the nerves and blood vessels can cause impotence. Conditions that can cause problems include:

  • Nerve dysfunction—can reduce feeling in the penis, resulting in impotence
  • Diabetes —interferes with nerve signals
  • Hardening of the arteries —can cause reduced blood flow
  • Peripheral neuropathy , spinal cord injury, and surgery—can damage nerves
  • Side-effects from medications
Blood Vessels and Nerves of Male Pelvis

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Psychological Factors
Many of the nerve signals needed for an erection come from the brain. Emotional problems may play a role in men who suddenly develop impotence.

Risk Factors
Impotence is more common in men who are 65 and older. It is also more common in men of Hispanic descent.

Factors that increase your chance of developing impotence include:

Symptoms include:

  • A less firm penis
  • Fewer erections
You will be asked about your symptoms and medical history. A physical exam will be done. Expect questions about the frequency, quality, and duration of your erections. Your answers may help the diagnosis.

Your bodily fluids may be tested. This can be done with blood tests.

Nocturnal Penile Tumescence Testing
This test will monitor erections while you sleep. Involuntary erections during sleep are normal. If you have impotence but have normal erections during sleep, the problem may be emotional. If you have problems with an erection even while you sleep, the problem may be physical.

Doppler imaging is used to look at the blood flow. The test is done to check for blood flow in the penis. It will also look for blockage in the arteries or veins that supply the penis.

Treatment options include:

Your doctor may prescribe:

  • Phosphodiesterase inhibitors
      Do not take these medications if you are also taking nitrates.

  • Oral testosterone , if you have low testosterone levels
  • Alprostadil , either injected into the penis or inserted into the urethra as a suppository
Use caution and talk to your doctor before taking any over-the-counter medications for impotence. Some of them may be unsafe.

Vacuum Devices
A vacuum device pulls blood into the penis. A band will then be placed around the penis to keep the erection. A vacuum device may include:

  • Plastic cylinder for the penis
  • Hand pump for pumping air out of the cylinder
  • Elastic band for holding the erection after removal of the cylinder
Vascular Surgery
Vascular surgery is done to repair the blood vessel leaks. This has been shown to be effective in some cases.

Penile Implants
Implants may be placed in the penis. The implants can be inflated to simulate an erection.

Penile Implant

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Sex Therapy
Sex therapy may help impotence resulting from:

  • Ineffective sexual techniques
  • Relationship problems
  • Anxiety
  • Depression
To reduce your chance of becoming impotent:

  • Follow treatment plans to manage blood pressure , diabetes, or depression.
  • Maintain a healthy weight .
  • Eat a healthful diet .
  • If you smoke, talk to your doctor about ways to quit . Smoking is significantly associated with impotence in older men.

Family Doctor—American Academy of Family Physicians

Urology Care Foundation

Canadian Urological Association

SexualityandU—Society of Obstetricians and Gynaecologists of Canada

Erectile dysfunction. EBSCO DynaMed website. Available at: Updated May 4, 2014. Accessed October 1, 2014.

Erectile dysfunction. National Institute of Diabetes & Digestive & Kidney Diseases website. Available at: Updated March 28, 2012. Accessed October 1, 2014.

Erectile dysfunction. Urology Care Foundation website. Available at: Updated 2009. Accessed October 1, 2014.

Viera A, Shenenberger D, Green G. Am Fam Physician. 1999 Sep 15;60(4):1159-66. Available at: Accessed October 1, 2014.

Last Reviewed August 2014

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