The underlying pathophysiology and causes of erectile dysfunction.

Physical organic causes are now thought to account for most cases of erectile dysfunction (ED), although there is often a psychogenic contribution to the condition. Atherosclerotic disease is estimated to account for 40% of ED in men over 50 years, and vascular disease, including diabetes, is a common cause of ED. ED may be considered an early marker for cardiovascular disease. Ageing is a strong risk factor, and both psychological conditions such as anxiety and depression and neurological conditions such as Parkinson's disease are also common risk factors. Pelvic surgery, with which there is a risk of nerve damage, may also result in ED. Other causes include endocrine disorders, and interactions from prescribed drugs such as antihypertensives, antidepressants, antipsychotics, hormone treatments, and histamine H2 antagonists such as cimetidine. Anatomical features and anatomical conditions such as Peyronie's disease are a less common cause of ED.