Over the past decades, the medical perspective on the causes of erectile dysfunction has shifted. Common wisdom used to attribute almost all cases of impotence to psychological factors. Now investigators estimate that up to 85% of impotence cases are caused by medical or physical problems. Only 15% are psychologically based.
It is often difficult to determine if the cause of erectile dysfunction is a physical or psychological one, or even some combination. The following may be helpful:
In virtually every case of erectile dysfunction there are emotional issues that can seriously affect the man's self-esteem and relationships. Negative emotions may even perpetuate erectile dysfunction that has been caused by a medical condition that has been successfully treated. Many men tend to fault themselves for their impotence even if it is clearly caused by physical problems over which they have little or no control.
Anxiety. Anxiety has both emotional and physical consequences that can affect erectile function. It is among the most frequently cited contributors to psychological impotence. Excessive concern about sexual performance is often referred to as performance or "honeymoon" anxiety and may provoke an intense fear of failure and self-doubt. It can sometimes set off a cycle of chronic impotence. In response to anxiety, the brain releases chemicals known as neurotransmitters that constrict the smooth muscles of the penis and its arteries. This constriction reduces the blood flow into, and increases the blood flow out of, the penis. Even simple stress may promote the release of brain chemicals that disrupt potency in a similar way.
Depression. Depression is strongly associated with erectile dysfunction. Depression can certainly reduce sexual desire, but it is often not clear which condition comes first.
Troubles in relationships often have a direct impact on sexual functioning. Partners of men with erectile dysfunction may feel rejected and resentful, particularly if the affected man does not confide his own anxieties or depression. Both partners commonly experience guilt for what they each perceive as a personal failure. Tension and anger frequently arise between people who are unable to discuss sexual or emotional issues with each other. It can be very difficult for the man to perform sexually when both partners harbor negative feelings.
Smoking contributes to the development of impotence, mainly because it increases the effects of other blood vessel disorders, including high blood pressure and atherosclerosis.
Alcohol has also been implicated in causing impotence. A small amount releases inhibitions, but having more than one drink can depress the central nervous system and impair sexual function.
Infrequent erections deprive the penis of oxygen-rich blood. Without daily erections, collagen production increases and eventually may form a tough tissue that interferes with blood flow. The spontaneous erections men have while sleeping or awake may be a natural protection against this process.
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