Erectile dysfunction or impotence is a sexual dysfunction characterized by the inability to develop or maintain an erection of the penis for satisfactory sexual intercourse regardless of the capability of ejaculation. There are various underlying causes, such as diabetes, many of which are medically reversible. The causes may be physiological or psychological. Psychological impotence can often be helped by almost anything that the patient believes in; there is a very strong placebo effect. ...
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Signs and symptoms
... Patterns of erectile dysfunction include: Occasional inability to obtain a full erection Inability to maintain an erection throughout intercourse Complete inability to achieve an erection
Source: MayoClinic

... The penis contains two cylindrical, sponge-like structures that run along its length, parallel to the tube that carries semen and urine (urethra). When a man becomes sexually aroused, nerve impulses c...
Source: MayoClinic

Risk factors
... A wide variety of physical and emotional risk factors can contribute to erectile dysfunction. They include: Physical diseases and disorders. Chronic diseases of the lungs, liver, kidneys, heart, nerve...
Source: MayoClinic

When to seek medical advice
... It''s normal to experience erectile dysfunction on occasion. But if erectile dysfunction lasts longer than two months or is a recurring problem, see your doctor for a physical exam or for a referral t...
Source: MayoClinic

Screening and diagnosis
... Your doctor will want to ask questions about how or when your condition developed, the medications you take and any other physical conditions you may have. Your doctor will also want to discuss recent...
Source: MayoClinic