Erectile dysfunction

Erectile dysfunction (ED or (male) impotence) is a sexual dysfunction characterized by the inability to develop or maintain an erection of the penis. There are various underlying causes, such as cardiovascular leakage and diabetes, many of which are medically treatable. Nerve trauma from prostatectomy surgery can cause chronic erectile dysfunction. The causes of erectile dysfunction may be physiological or psychological. Physiologically, erection is a hydraulic mechanism based upon blood entering and being retained in the penis, and there are various ways in which this can be impeded, most of which are amenable to treatment. Psychological impotence is where erection or penetration fails due to thoughts or feelings (psychological reasons) rather than physical impossibility; this can often be helped. Notably in psychological impotence, there is a very strong placebo effect.