The term “erectile dysfunction” refers to the inability to achieve and maintain an erection that allows satisfactory sexual intercourse. Unlike most primates, erection in humans is achieved entirely by a vascular mechanism. During arousal, the two cavernous bodies of the penis (also called corpora cavernosa) fill with blood. Their structure allows the retention of blood in their cavities with a rise in the pressure in them to about 100 mmHg (phase of full erection). The contraction of the pelvic musculature further raises the pressure in the corpora cavernosa to 500 mmHg and, accordingly, the hardness of the penis (phase of rigid erection). With a full erection, the circumference at the base of the penis increases by 3 cm, and at the tip by 2 cm. After orgasm and ejaculation, the so-called detumescence. Penile relaxation is associated with rapid swelling of blood in the venous system. Upon contraction of the smooth muscles located between the cavities of the cavernous bodies, the retained blood is drained and the unexcited state of the penis is restored. Erection is the key and perhaps the most vulnerable part of male sexuality. It depends on many factors – vascular, nervous, hormonal, metabolic and mental, which interact with each other. Erection problems can be due to organic reasons: neurogenic, vascular, hormonal, anatomical, and often they are superimposed on mental factors. What diseases lead to erectile dysfunction? Erectile dysfunction is a common symptom of many diseases, among which the most important are diabetes mellitus, arterial hypertension and metabolic disorders. Diabetes mellitus can cause erectile dysfunction by several mechanisms – by disrupting the penile vessels, nerve endings and endothelial cells, which are necessary for the release of the main neurotransmitter for arousal – nitric oxide. Disturbances of lipid metabolism are also related to the pathogenesis of erectile dysfunction and, in particular, the increase in total and bad cholesterol (LDL) levels. Between 50-80% of cases of organic erectile dysfunction are due to disorders in the arterial blood supply to the penis, due to atherosclerotic changes or vessel injury. NEWS_MORE_BOX Penile arteries have a smaller diameter compared to the wider vessels of the heart, therefore the accumulation of atherosclerotic plaques in them occurs earlier. Erectile dysfunction precedes the onset of symptoms of coronary artery disease and cardiovascular incident by 2-3 and 3-5 years, respectively. This makes vascular erectile dysfunction an early harbinger of a heart attack or stroke. Veno-occlusive dysfunction can often be found in diabetes mellitus, after trauma or surgery in the penile area, or in old age. In it, there is a rapid swelling of the blood from the cavities of the cavernous bodies due to the inability to close the veins during erection or due to the presence of ectopic veins, being an alternative route for blood swelling.Neurological causes of erectile dysfunction include spinal cord injuries, peripheral neuropathies, etc. Alcohol in small quantities has a vasodilating effect, which improves erection and further suppresses anxiety. However, with excessive use, it exerts a central sedative effect, can weaken the libido and lead to transient erectile dysfunction. Chronic alcoholism causes hypogonadism and polyneuropathy of the nerve endings of the penis. The list of drugs that can cause erectile dysfunction is long. At least 25% of cases are due to them. These are antidepressants; antipsychotics; anxiolytics; antiarrhythmic drugs; some of the antihypertensive agents, such as beta-blockers (propranolol), centrally acting alpha-agonists (clonidine), thiazide diuretics; drugs; antimycotics; lipid-lowering agents; corticosteroids, etc.