Normal penis and erection
The penis has two chambers that are spongy in nature called the corpora cavernosa. During sexual arousal and erection nerve impulses from the brain and from the local nerves lead to relaxation of the muscles in the corpora cavernosa and this allows blood to flow in and fill the spaces within the tissue. This raises the pressure within the penis and causes it to expand. The blood is trapped in the corpora cavernosa by a membrane called the tunica albuginea and thus a normal erection is maintained.
The erection stops when the muscles contract to stop blood flowing into the penis and open the channels that lead to outflow of the blood from the penis. The whole process is synchronized and anything which disrupts this sequence can lead to problems either starting or maintaining an erection.
Symptoms of erectile dysfunction or impotence
The main symptom of erectile dysfunction is the inability to get and maintain an erection for satisfactory intercourse.
There are other problems that may or may not be related or associated with erectile dysfunction. This includes ejaculation problems such as premature ejaculation, which is a condition where the process of arousal, orgasm and ejaculation occurs very rapidly. Premature ejaculation may have similar impact on the psychological well being and quality of life but is a separate disorder. Impotence and premature ejaculation should not be confused.
Inability to get an erection
Patients commonly complain of inability to get an erection. This may be specific as well. The individual may get an erection on waking up or while masturbating while fail to get or maintain an erection with a sexual partner. In these circumstances, it is likely that the underlying cause of the condition is primarily psychological or stress related. In case an individual is unable to get an erection under any circumstances the condition is likely to have a purely physical cause.
Inability to maintain an erection
Many individuals with the condition complain of getting an erection but being unable to maintain it long enough to achieve a satisfactory sexual intercourse.
History of changes
History of changes in relationships, surgery, and radiation to the pelvis or scrotum, certain drugs use, smoking, high alcohol consumption, use of recreational or body-building drugs long standing diabetes, high blood pressure or cholesterol is also significant. There may be presence of peripheral vascular disease and reduced flow of blood to the penis. There may also be a venous leak.
History of hormonal disorders
History of hormonal disorders like pituitary gland tumors or abnormal levels of testosterone may be present. Presence of cavernosal disorders like Peyronie's disease.
Presence of psychological causes
These can include stress, mental disorders such as depression, schizophrenia, substance abuse, panic disorder, generalized anxiety disorders, personality disorders or traits and low self esteem.
History of prostate and bladder cancer
History of prostate and bladder cancer that has required removing tissue and nerves surrounding a tumor also increases the risk for impotence.
Changes in libido