Physical Causes:

A number of conditions share a common problem with erectile dysfunction -- the impaired ability of blood vessels to open and allow normal blood flow.

The following conditions are highly associated with erectile dysfunction:

Heart Disease

Heart disease, atherosclerosis, and high cholesterol levels are major risk factors for erectile dysfunction. In fact, erectile problems may be a warning sign of these conditions in men at risk for atherosclerosis. Men who experience ED may have a greater risk for angina, heart attack, or stroke. Patients with ED should be evaluated for cardiovascular problems. [For more information, see In-Depth Report #3: Coronary artery disease.]

High Blood Pressure (Hypertension)

Erectile dysfunction is a very common problem in men with high blood pressure, possibly because of the age group itoccurs in. More than 40% of men with erectile dysfunction have hypertension. The disease process is the major contributor to impotence, but many of the drugs used to treat hypertension (such as calcium channel blockers and beta-blockers) also cause it. [For more information, see In-Depth Report #14: High blood pressure.]

Diabetes

Diabetes is a major risk factor for erectile dysfunction. Between 30 - 50% of all men with diabetes report some form of sexual difficulty. Blocked arteries and nerve damage are both common complications of diabetes. When the blood vessels or nerves of the penis are involved, erectile dysfunction can result. Diabetes is also associated with heart disease, another risk factor for ED. [For more information, see In-Depth Report #60: Diabetes type 2.]

Obesity

Obesity increases the risk for diabetes, heart disease, and erectile dysfunction.

Metabolic Syndrome

Metabolic syndrome -- a cluster of conditions that includes obesity and abdominal fat, unhealthy cholesterol and triglyceride levels, high blood pressure, and insulin resistance -- is also a risk factor for erectile dysfunction in men older than 50 years.

Benign Prostatic Hyperplasia

Lower urinary tract symptoms associated with benign prostatic hyperplasia can decrease nitric oxide in the penis. Surgery and drug treatments, such as finasteride (Proscar), can also increase the risk for impotence. [For more information, see In-Depth Report #71: Benign prostatic hyperplasia.]

Neurologic Conditions

Diseases that affect the central nervous system can cause erectile dysfunction. These conditions include Parkinson’s disease, multiple sclerosis, and stroke. [For more information, see In-Depth Reports #51: Parkinson’s disease; #17: Multiple sclerosis; #45: Stroke.]

Endocrinologic and Hormonal Conditions

Low levels of the male hormone testosterone can be a contributing factor to erectile dysfunction in men who have other risk factors. (Low testosterone as the sole cause of erectile dysfunction affects only about 5% of men. In general, low testosterone levels are more likely to reduce sexual desire than to cause impotence.) Abnormalities of the pituitary gland that cause high levels of the hormone prolactin are also associated with erectile dysfunction. Other hormonal and endocrinologic causes of erectile dysfunction include thyroid and adrenal gland problems.

A varicocele is an enlarged (varicose) vein in the cord that connects to the testicle. Varicoceles are found in 15 - 20% of all men and in 25 - 40% of infertile men. When varicoceles occur in both testicles, they may contribute to hormone imbalances that cause erectile dysfunction.

Physical Trauma and Injury

Spinal cord injury and pelvic trauma, such as a pelvic fracture, can cause nerve damage that results in impotence. Other conditions that can injure the spine and effect impotence include spinal cord tumors, spina bifida, and a history of polio.

Surgery

Surgery for Prostate Cancer. Radical prostatectomy can cause loss of sexual function. Nerve-sparing surgical procedures are proving to be helpful in reducing the risk of impotence. (Radiation treatments for prostate cancer, especially external-beam radiation, may cause fewer problems than surgery.) [For more information, see In-Depth Report # 33: Prostate cancer.]

Surgery for Colon and Rectal Cancers. Surgical and radiation treatments for colorectal cancers can cause impotence in some patients. In general, colostomy does not usually affect sexual function. However, wide rectal surgery can cause short-term or long-term sexual dysfunction. [For more information, see In-Depth Report #55: Colon and rectal cancers.]

Surgical Treatment of Inflammatory Bowel Disease. Rectal excision for inflammatory bowel disease (IBD) can cause impotence, but rates are low (2 - 4%).

Fistula Surgery. Surgery to repair anal fistulas can affect the muscles that control the rectum (external anal sphincter muscles), sometimes causing impotence. (Repair of these muscles may restore erectile function.)

Orthopedic Surgery. Erectile dysfunction can sometimes result from orthopedic surgery that affects pelvic nerves.

Note: Vasectomy does not cause erectile dysfunction.

Medications

Many medications increase the risk for erectile dysfunction. They include:

• High blood pressure medications, particularly diuretics, beta-blockers, and calcium-channel blockers.
• Heart or cholesterol medications such as digoxin, gemfibrozil, or clofibrate.
• Psychotropic medication used to treat depression and bipolar disorder such as selective serotonin-reuptake inhibitors (SSRIs), tricyclic antidepressants, monoamine oxidase inhibitors, and lithium. Certain types of antipsychotic medication, such as phenothiazines (like compazine) and butyrophenones (like haloperidol), can also cause erectile dysfunction.
• Gastroesophagelal reflux disorder (GERD) medications, used to reduce stomach acid, such as rantidine (Zantac) and cimetidine (Tagamet).
• Hormone drugs such as estrogens, corticosteroids, and 5-alpha reductase inhibitors.
• Chemotherapy drugs such as methotrexate.

Other Problems in Sexual Function

Premature Ejaculation. Premature ejaculation is the most common male sexual dysfunction and occurs in as many as 40% of men. It is defined as the inability to delay ejaculation to the point where both partners are satisfied. This can vary widely depending on the preferences of the partners. Younger men tend to have this problem more than older men. Anxiety is a major factor at any age. In general, the longer the duration between ejaculations, the faster they are. Various techniques are available to help delay orgasm.

The standard medications used for this condition are selective serotonin reuptake inhibitors (SSRIs), which include Prozac and Paxil. Some studies suggest that sildenafil (Viagra) in combination with an SSRI may be helpful. There is still no drug specifically approved for treating premature ejaculation.

Peyronie's Disease. Peyronie's disease is an accumulation of scar tissue within the penis shaft, which causes it to curve. The curvature can make erection and intercourse difficult and painful. This condition may be associated with an injury to the penis, but no clear information exists on its origin. The disease often goes into a type of spontaneous remission, and some individuals who had previously experienced erectile dysfunction are able to resume sexual activity. Scarring may still cause erection problems, however, even in these cases.

Treatment options include oral drugs, injections, and surgery. Penile implants may also be beneficial.

Not all men need treatment for Peyronie’s disease. Sometimes the condition improves on its own without treatment.

Priapism. Priapism is a sustained, painful, and unwanted erection that persists despite a lack of sexual stimulation. Generally, priapism results when the smooth muscle tissue remains relaxed so that a constant flow of blood into the vessels of the penis occurs with no leakage back out. The development of priapism has been associated with urinary stones, certain medications, neurologic disorders, and, more recently, with self-injection therapy used for impotence.

If priapism occurs, applying ice for 10-minute periods to the inner thigh may help reduce blood flow. Erections that last 4 hours or longer require emergency care.