Persistent or recurrent inability to attain, or to maintain until completion of sexual activity, an adequate erection. This is also know as erectile dysfunction.

The disorder may cause marked distress or interpersonal difficulty. There are different patterns. Some individuals report inability to obtain erection from the beginning of sexual experience; while others report being able to experience erection only during masturbation or on awakening, but not during the coitus. Some experience adequate erection, lose it when attempting penetration. Still other report that they have an erection that is sufficiently firm for penetration, but they lose erection before or during thrusting.

Male erectile disorder is frequently associated with anxiety, fear of failure, pressure of sexual performance, and decreased sexual excitement and pleasure. This can disrupt marital relationship and may be the cause of unconsummated marriage and infertility.

Causes: 

Ageing: With advancing age,

  • The orgasm is less intensive,
  • The ejaculate is reduced
  • The interval between the two successive acts is increased.

Psychological factors: 

  • Fatigue,
  • Depression,
  • Stress,
  • Mental disorders,
  • Guilt,
  • Fear of failure,
  • Low self esteem
  • Religious restrictions
  • Homosexuality
  • Long/serious illness
  • Traumatic initial experience
  • Negative feelings towards the partner
  • Vascular causes
  • Use of tobacco/Alcohol
  • Atherosclerosis
  • Peyronie’s disease
  • Diabetes
  • Hypertension
  • Venous leak or occlusion
  • Trauma
  • Surgery
  • Radiation

Hormonal causes: 

  • Hypogonadism
  • Hyperprolactinemia
  • Diabetes
  • Thyroid disease
  • Androgen deficiency
  • Estrogen excess 
  • Adrenal pituitary of Hypothalamic disease

Neurogenic causes:

  • Peripheral Neuritis
  • Autonomic neuropathy (in Diabetes)
  • Multiple sclerosis
  • Spinal cord disease

Drug related causes:

  • Antiandrogens
  • H2receptor antagonists
  • Diuretics
  • Antihypertensive
  • Anticholinergics
  • Antidepressants
  • Antipsychotics
  • CNS Depressants
  • Substance abuse

Miscellaneous:

  • Renal failure
  • Prostatectomy

Diagnostic tests

Stamp Test: A long strip of postal stamps is wound around the base of the penis at night before going to bed. Next morning if the perforations of the strip are found to be torn off, impotence is supposed to be of psychological in origin.
Peno-brachial index: The ratio of penile systolic blood pressure to that of brachial systolic blood pressure is normally 0.6. If found to be low, impotence is vascular in origin. 
Papaverine Injection Test:  Papaverine is a vasoactive drug. Using a 26 gauge needle, 30 mg papaverine is injected at the mid-shift of Corpus cavernosum of penis. He is isolated, asked to stoke the penis and expose to erotic literature. Erection will occur in 10 to 15 minutes. If the erection is short-lived or partial, then impotence is considered as vasculogenic.  If the erection is full, then impotence is considered to be neurogenic or psychogenic in origin.

Caution : This test should be performed in a hospital setting or where the facilities for detumescence  are available. The patient should be observed for next few hours till the erection subsides.
Rigiscan Test: This is a gold standard for evaluation of Nocturnal Penile Tumescence and Rigidity (NPTR). This test is based on the physiological principle that a male gets erection 3 to 5 times during REM sleep. At night, before going to sleep one ring of Rigiscan is slid over the base of the penis and the over the tip. Next morning, the tracing obtained are studied. This test can quantify erectile tumescence and rigidity. Rigiscan tracing indicates whether the impotence is organic or psychological in origin.
Arterial insufficiency  and venous leaks can also be suspected on the basis of Rigiscan graphs. Patients with purely artery disease have low levels of rigidity but of adequate duration. Patients with venous leak will have varying rigidity levels with shortened duration.
Penile Ultrasound : This test is for evaluation of functioning of the penile areteries. A simple acoustic Doppler emits auditory signals or a colour Doppler can help visualization of arteries. 
Cavernosometry  & cavernosography: This haemodynamic  test is useful for diagnosing veno-occlusive dysfunction of the corpora. 
Biothesiometry, electromyography , nerve conduction studies: These are for evaluation of neurogenic impotence.

Treatment
Counseling

Sexual dysfunction is a marital unit problem and therefore both, husband and wife, should attend. Counselling is towards strengthening marital relationship. Wife is requested to co-operate. Client is requested to quit smoking and alcohol. He is advised relaxation exercise, yoga. The couple is educated about anatomy, physiology of sexual organs sexuality are countered. Their myths and misconceptions about  sexuality are countered. They are also explained that he does not have to do anything to have an erection. Erection is a physiological response to effective stimuli.