The term impotence just means weakness (or lack of potency, if you will) but in common speech usually refers to erectile dysfunction; which is the inability to achieve or maintain an erection. In this article when I use the word impotence I am using it in this regard to describe erectile dysfunction. Another thing that the word impotence is associated with is elderly men, and while the problem is more common among men over fifty it can affect men of all ages.
There is more than one cause for impotence, and the factors are not always physical. A major factor in impotence, especially in younger men, is psychological. Being under a great amount of stress can make it difficult to become aroused, as well as feeling of depression or anger. In fact, anxiety disorders may very well be a leading cause of impotence; and impotence increases anxiety, which makes impotence more likely to occur and this can go around in a quick downward spiral. Nervousness about the sex act itself can cause impotence. Feelings of guilt, either related or unrelated to sex, can also cause impotence.
The use of alcohol and some drugs is definitely a major cause of both temporary and long term impotence. Most men who have indulged in more than three or four drinks at one occasion can testify to this (though they probably wouldn't publically). This is because alcohol is a depressant of the central nervous system, and therefore makes the nerve endings in the penis far less sensitive. Long term alcohol abuse can lead to problems producing testosterone, which also becomes a form of impotence. Other than drinking liquor, cigarettes can cause impotence by restricting blood flow to the penis (something I will discuss in detail shortly) and it has been speculated than marijuana can cause short term impotence. Of course many prescription drugs have unwanted side effects, and sometimes these are sexual side effects. Pharmaceuticals used in the treatment of male pattern baldness are a good example of this. Antidepressants and anti-anxiety medications have been known to cause impotence as well (though sometimes it is the depression and anxiety itself which is causing impotence rather than the medication).
Nerve damage is a less common cause of impotence but does occur. This can either be damage to the nerve endings in the penis, a spinal cord injury, or a chemical malfunction in stimulating the nervous system. Unfortunately, this is the most difficult for of impotence to cure or treat.
The most common cause of impotence by far is decreased blood flow. The inside of the penis contains the urethra and a series of chambers with a spongy tissue inside called the corpus cavernosum. When one stimulated blood begins flowing to the penis and fills up these chambers and is absorbed by the spongy tissue so that it expands and becomes firm. No blood flow, no erection. This is a treatable condition, and the treatment for this type of impotence is available without a prescription. There are herbal supplements which can greatly improve blood flow to the penis to cure this type of impotence. Though they have been around for quite a long time, it was only until the invention of Viagra that people started to believe a pill could cure impotence and started looking for a natural alternative to Viagra. While the problems of nerve damage, substance abuse and psychological problems are difficult to deal with, poor blood flow is not and should be no reason to live with impotence.