Men with a physical cause for ED frequently experience the same sort of psychological reactions such as stress, anxiety, guilt, depression. The other surprising causes are smoking. Smoking affects blood flow in veins and arteries, and hormonal abnormalities, such as not enough testosterone which can lead to ED. If you notice any problems, the first thing to do is quit smoking and talk to your doctor.

Your doctor will ask general questions about your health, as well as specific questions about your erection problems and your relationship with your partner. Bring a list of all the medications you take, or bring them with you to show to your doctor. Tell your doctor about any surgery you have had.

Your doctor will ask about habits like alcohol use, smoking, and exercise.

Your doctor might ask you questions like

• How do you rate your confidence that you can get and keep an erection?
• When you have erections with sexual stimulation, how often are your erections hard enough for penetration?
• During sexual intercourse, how often are you able to maintain your erection after you have penetrated (entered) your partner?
• When you attempt sexual intercourse, how often is it satisfactory for you?
• How would you rate your level of sexual desire?
• How often are you able to reach climax and have an ejaculation?
• Do you have an erection when you wake up in the morning?

The answers to these questions will help your doctor understand the problem.

Physical Exam

A physical exam can help your doctor find the cause of your ED. As part of the exam, the doctor will examine your testes and penis, take your blood pressure, and check your reflexes. A blood sample will be taken to test for diabetes, cholesterol level, and other conditions that may be associated with ED.

Source: National Kidney and Urologic Diseases Information Clearinghouse

Medical and sexual histories help define the degree and nature of ED. A medical history can disclose diseases that lead to ED, while a simple recounting of sexual activity might distinguish among problems with sexual desire, erection, ejaculation, or orgasm.

Using certain prescription or illegal drugs can suggest a chemical cause, since drug effects account for 25 percent of ED cases. Cutting back on or substituting certain medications can often alleviate the problem.

Physical Examination

A physical examination can give clues to systemic problems. For example, if the penis is not sensitive to touching, a problem in the nervous system may be the cause. Abnormal secondary sex characteristics, such as hair pattern or breast enlargement, can point to hormonal problems, which would mean that the endocrine system is involved. The examiner might discover a circulatory problem by observing decreased pulses in the wrist or ankles. And unusual characteristics of the penis itself could suggest the source of the problem, for example, a penis that bends or curves when erect could be the result of Peyronie’s disease.

Laboratory Tests

Several laboratory tests can help diagnose ED. Tests for systemic diseases include blood counts, urinalysis, lipid profile, and measurements of creatinine and liver enzymes. Measuring the amount of free testosterone in the blood can yield information about problems with the endocrine system and is indicated especially in patients with decreased sexual desire.

Other Tests

Monitoring erections that occur during sleep (nocturnal penile tumescence) can help rule out certain psychological causes of ED. Healthy men have involuntary erections during sleep. If nocturnal erections do not occur, then ED is likely to have a physical rather than psychological cause. Tests of nocturnal erections are not completely reliable, however. Scientists have not standardized such tests and have not determined when they should be applied for best results.

Psychosocial Examination

A psychosocial examination, using an interview and a questionnaire, reveals psychological factors. A man’s sexual partner may also be interviewed to determine expectations and perceptions during sexual intercourse.

Source: National Institute of Diabetes and Digestive and Kidney Diseases

Damage to nerves, arteries, smooth muscles, and fibrous tissues, often as a result of disease, is the most common cause of ED. Diseases such as diabetes, kidney disease, chronic alcoholism, multiple sclerosis, atherosclerosis, vascular disease, and neurologic disease account for about 70 percent of ED cases. Between 35 and 50 percent of men with diabetes experience ED.

Lifestyle choices that contribute to heart disease and vascular problems also raise the risk of erectile dysfunction. Smoking, being overweight, and avoiding exercise are possible causes of ED.

Also, surgery (especially radical prostate and bladder surgery for cancer) can injure nerves and arteries near the penis, causing ED. Injury to the penis, spinal cord, prostate, bladder, and pelvis can lead to ED by harming nerves, smooth muscles, arteries, and fibrous tissues of the corpora cavernosa.

In addition, many common medicines blood pressure drugs, antihistamines, antidepressants, tranquilizers, appetite suppressants, and cimetidine (an ulcer drug) can produce ED as a side effect.

Experts believe that psychological factors such as stress, anxiety, guilt, depression, low self-esteem, and fear of sexual failure cause 10 to 20 percent of ED cases. Men with a physical cause for ED frequently experience the same sort of psychological reactions (stress, anxiety, guilt, depression). Other possible causes are smoking, which affects blood flow in veins and arteries, and hormonal abnormalities, such as not enough testosterone.

Source:  National Kidney and Urologic Diseases Information Clearinghouse