Erectile dysfunction and impotence are the names of the recognized medical condition with which a man is unable to develop or keep an erection. Erections develop as a result of friction in the penile shaft, and this can be achieved by directly stimulating the area or brought on involuntarily by erotic psychological stimuli. There are certain physical requirements of achieving an erection by either of these mechanisms.
These include a healthy neural system, pituitary glands and testosterone-producing testes. There are numerous medical conditions that can be responsible for erectile dysfunction, and many of these can be treated and cured. Diabetes is not an uncommon condition and is known to cause impotence in 35-50% of cases.
Other causes include cardiovascular diseases, hormone deficiencies resulting in low levels of testosterone, neuropathy and disease or damage to the pituitary glands, testes or neural system. Erectile dysfunction is also listed as a side-effect of using various drugs, including those that treat the central nervous system, high blood pressure or psychological problems.
Long term use of SSRIs has been known to result in long-term erectile dysfunction, known as Post SSRI Sexual Dysfunction. A poor diet, weight problem, lack of exercise and/or alcoholism are other common causes of impotence.
However, most instances of erectile dysfunction have a psychological root; and in the cases of men who have not completely lost their ability to achieve an erection (they can do so when sleeping, for example), this is certainly the case.
Psychological impotence can be the result of worry, unhappiness or exhaustion and is very, very rarely permanent. Psychological impotence is listed in the definitive medical manual as a 'mental disease', although the condition is known to be effectively treated by placebos.
Sildenafil citrate is the active ingredient in the first pill to be approved by the US health authority for the treatment of erectile dysfunction. The drug is commonly sold as Viagra, but also appears under the trade name of Cialis.