The goals of patient evaluation, are to assess the likely cause of the erectile dysfunction and identify medical or psychologic conditions that may be contributing to the dysfunction or that may influence treatment options.

Evaluation of Patient with Erectile Dysfunction

*--Screening panel: complete blood count, urinalysis, renal function, lipid profile, fasting blood sugar, and thyroid function.

†--First-morning, free testosterone level.

Algorithm for the evaluation and management of patients with erectile dysfunction.

Algorithm at the bottom. Click here

Often one can get an excellent clue to the etiology by the history and physical examination which can then be tested by precise laboratory tests. At the same time, some have multiple causes, such as a person with diabetes who is also on certain antihypertensive medications. It is essential to see that the evaluation is comprehensive without having a "Test…because a test is available!" approach.

Anatomic, psychogenic, endocrinologic, neurologic, and vascular abnormalities may all contribute to impotence. Therefore, the evaluation of impotence begins with a comprehensive history and physical examination.

Causes of Erectile Dysfunction and Diagnostic Clues



Physical Examination

Possible laboratory findings

Vascular Coronary artery disease; hypertension; claudication; dyslipidemia; smoking Decreased pulses; bruits; elevated blood pressure; cool extremities Abnomal lipid profile Abnormal penile-brachial pressure index
Diabetes mellitus Known diabetes; polyuria; polydipsia;polyphagia Peripheral neuropathy; retinopathy; abnormal body mass index Abnormal fasting blood glucose
Hypogonadism Decreased libido; fatigue Bilateral testicular atrophy; scant body hair; gynecomastia Decreased morning
free testosterone
Increased LH
Increased FSH
Hyperprolactinemia Decreased libido; galactorrhea; visual complaints; headache Bitemporal hemianopsia Elevated prolactin
Abnormal CT or
MRI scans of pituitary gland
Hypothyroidism Fatigue; cold intolerance Goiter; myxedema; dry skin; coarse hair Increased TSH
Decreased free T4
Hyperthyroidism Heat intolerance; weight loss; diaphoresis; palpitations Lid lag; exophthalmos; hyperreflexia; tremor; tachycardia Decreased TSH
Increased free T4
Cushing's syndrome Easy bruising; weight gain; corticosteroid use Truncal obesity; "moon face"; "buffalo hump"; striae Elevated overnight
suppression test
Alcoholism Excessive alcohol use; social, economic or occupational consequences of alcohol abuse; withdrawal symptoms Positive CAGE screen; thin body habitus; palmar erythema; spider telangiectasias; gynecomastia; tremor Abnormal hepatic
Decreased albumin
Macrocytic anemia
Neurologic Spinal cord injury; nerve injury (prostate surgery); stroke; peripheral neuropathy; incontinence; multiple sclerosis; Parkinson's disease Motor or sensory deficits; aphasia; gait abnormality; abnormal bulbocavernosus reflex; tremor
Mechanical Genital trauma or surgery; Peyronie's disease; congenital abnormalities Fibrous penile plaques or chordae None
Psychogenic Nocturnal erections; sudden onset; history of depression; anhedonia; poor relationship with partner; anxiety; life crisis Sad or withdrawn affect; tearful; psychomotor retardation Nocturnal penile tumescence (stamp test; Snap-Gauge) Positive depression inventory (Beck's)
Pharmacologic Inquire about all prescription and nonprescription drugs

A thorough history is the most important factor in the evaluation of the patient with erectile dysfunction. The initial step is to identify the patient's concern with his sexual function. A careful sexual history and knowledge of concurrent illnesses and medications are essential. The sexual history should include the duration of impotence, level of libido, and a complete inventory of sexual partners. The sexual history is often the most helpful piece of information in directing further evaluation and treatment.

Psychogenic disorders may occasionally be primary factors contributing to erectile dysfunction. In order to improve treatment for patients with psychogenic impotence, Lue has suggested classifying psychogenic impotence into 5 broad categories:

  • anxiety and fear of failure;
  • depression;
  • marital conflict or strained relationship;
  • ignorance or misinformation about normal anatomy and sexual function; and
  • obsessive-compulsive personality disorder, anhedonia, sexual deviation, and psychotic disorders. Recognition of these patient characteristics should lead the clinician to entertain the possibility of a primary psychogenic etiology of impotence.

Once a concern with the patient's sexual function is identified, the next step is to differentiate erectile dysfunction from other sexual problems, such as loss of libido or ejaculatory problems. The physician should use appropriate vocabulary, avoiding slang or excessively technical terminology. Having the patient define the terms in his own words will help the physician and patient communicate more effectively. The International Index of Erectile Function (IIEF) is a valuable tool for defining the area of sexual dysfunction. The IIEF is designed to be a self-administered measure of erectile dysfunction, but it also assesses a patient's function in other phases of sexual function. The IIEF also establishes a reliable baseline that can be used to monitor changes related to treatment.

The full 15 question IIEF which helps in distinguishing what type of sexual dysfunction is present can be accessed here.

The shortened 5 question IIEF which helps in judging the severity of true erectile dysfunction can be accessed here.

Early recognition of psychogenic disturbances allows the physician to avoid costly and confusing evaluation for other etiologies of impotence. Moreover, many patients complain of erectile dysfunction when they mean something lese such as premature ejaculation etc., and again this needs to be recognized before embarking on the detailed evaluation.

Because impotence is known to be associated with many common medical conditions and medications, a careful medical history may yield insights into the etiology of impotence. A history of peripheral vascular disease, coronary artery disease, diabetes, renal failure, tobacco and/or alcohol use, or psychogenic, neurologic, or other chronic debilitating diseases is often very helpful in directing further evaluation and treatment. Many common medications such as psychotropic drugs and antihypertensives have been associated with impotence. Similarly, a patient's surgical history may also provide clues to the possible causes of impotence. Prior radical pelvic surgery (eg, prostatectomy, abdominoperineal resection), radiation, and pelvic trauma are known to be associated with impotence.

The physical examination should assess the patient's overall health. Particular attention should be given to the cardiovascular, neurologic and genitourinary systems, as these systems are directly involved with erectile function.

Careful physical examination with particular attention to sexual and genital development may occasionally reveal an obvious cause of impotence. Careful examination of the penis may reveal an anatomic abnormality such as a micropenis, the presence of chordee, or a Peyronie's plaque. The finding of small, soft, atrophic testes (the typical adult testis is 4.5 cm long with a range of 3.5 to 5 cm.) or gynecomastia should prompt an endocrine evaluation for hypogonadism (beard, body hair and voice should be evaluated for signs of hypogonadism) or hyperprolactinemia. Certain genetic syndromes such as Kallmann's or Klinefelter's syndrome may present with obvious physical signs of hypogonadism or distinctive body habitus. The prostate gland should be assessed for size, consistency and symmetry.

The cardiovascular examination should include assessment of vital signs (especially blood pressure and pulse) and signs of hypertensive or ischemic heart disease. Abdominal or femoral artery bruits and asymmetric or absent lower extremity pulses are indicative of vascular disease. Skin and hair pattern evidence of vascular insufficiency should be noted.

A careful neurologic examination should also be performed on all patients. Patients with diabetes or neurodegenerative disorders may show evidence of peripheral neuropathy. Several reflexes can be tested to evaluate sacral cord function. The superficial anal reflex, indicative of normal somatic function of sacral cord levels S24, is assessed by touching the perianal skin and noting contraction of the external anal sphincter muscles. The bulbocavernosus reflex also demonstrates normal sacral cord function. It is performed by placing a finger in the rectum and noting contraction of the anal sphincter and bulbocavernosus muscle when the glans penis is squeezed. External anal sphincter tone can be assessed during this maneuver as well.

In many cases, a careful history and physical exam will direct the physician to the most expedient cost-effective evaluation and eliminate the need for unnecessary diagnostic tests.