Unwana and Sunday O Awofisayo
Department of Clinical Pharmacy and Biopharmacy, Faculty of pharmacy, University of Uyo
Department of Clinical Pharmacy and Biopharmacy, Faculty of Pharmacy, University of uyo
Erectile dysfunction (ED) also called impotence is characterized by the inability of the man to develop or maintain an erection of sufficient rigidity for satisfactory sexual intercourse. Erection occurs when blood flows into the penis thereby increases it making the penis larger and firmer. The combinations of hormones, blood vessels, nerves and muscles all work together to cause an erection. When the brain senses a sexual urge, it starts an erection by sending nerve signals to the penis. The nerve signal causes the muscles in the penis to relax and allows blood flow into the sponge tissues in the penis. Blood collects in this tissue like water filling a sponge. The penis becomes larger and firmer like a blown up balloon. The vein shut off to keep blood from flowing out. An erection requires healthy blood vessels. After orgasm or when the man is no longer aroused, the veins open up and blood flows back into the body. This review examines the failure of the penis to function this way leading to erectile dysfunction.
Erectile dysfunction has been profoundly defined as the inability to achieve or maintain an erection sufficiently rigid for satisfying sexual intercourse ( ). Erectile dysfunction can have a profound negative impact on the quality of life and life satisfaction of the patient resulting in fear, loss of self image and self confidence and depression. Erectile dysfunction can occur if one gets an erection sometimes and not every time or an erection that does not last enough for sex or unable to get an erection at all.
An estimated 150 million men worldwide have some degree of ED and more than twice that many are expected to be affected by 2025 ( ). The exact number of persons with ED may be underestimated by reason of the stigma that goes with the disease. In Africa , surveys of men between the ages of 35 and 70 years requesting primary medical care indicated that the prevalences of ED were 57.4% in Nigeria and 63.6% in Egypt ( ).
CAUSES OF ERECTILE DYSFUNCTION
Neurological problems resulting from trauma to the parasympathetic nerves from prostate surgical procedures have suffered ED. A number of cases of persons from post surgery experiences of ED have been documented. In the same vein, drugs such as nozotine, alcohol and antidepressants have been reported as causes of Ed ( ).
In men older than age 40, ED is most often caused by an underlying vascular disease. As discussed previously adequate blood flow is essential for penile erection. Vascular disease which can occur as a result of uncontrolled hypertension, Diabetes Mellitus and artherosclerosis reduce the ability of the body’s blood vessels including those in the penis to dilate ( ). Part of this impaired vasodilation is due to decreased release of nitric oxide ( ).
Psychological conditions such as stress, anxiety and depression can contribute to ED ( ). Prolonged bicycling which compress the nerves and affect blood to the penis can lead to temporary ED.
COMPLICATIONS OF ERECTILE DYSFUNCTION
Erectile dysfunction can lead to various complications such as impotence, embarrassment, low self esteem, loss of confidence and fear.
In the treatment of erectile dysfunction, there are non pharmacological and pharmacological treatments. Non pharmacological treatment involves advising the patient on the underlying cause of the dysfunction, and low to do away with these underlying causes. The following measures including abstinence from alcohol, eating of food that will increase nitric oxide formation. Nitric oxide has been documented to be of immense importance to the functionality of the physiology of the Penis. Treatment of the hypertension and diabetes if present is of utmost importance in the management of ED. Exercise improves the flow of blood to the penis and this has been reported to be of advantage. Healthy eating habits and meals containing fruits and vegetables are advantageous. Smoking and the use of illegal drug are deleterious and are associated with ED.
This involves the use of drug which are divided into 3 classes namely the phosphoodiesterase inhibitors including sidenafil (viagra, vega, embagra), vardenafil and tadalafil (tadalis, honinhil).
MODE OF ACTION
Tadalafil is used as a treatment for adult men with ED. It contains the active substance tadalafil which belongs to a group of medicines called phosphodiesterase type 5 inhibitor. Following sexual stimulation it works by helping the blood vessels in your penis to relax, allowing the flow of blood into your penis.. Common side effects are headache, indigestion, facial flushing, muscle pain, back pain, nasal congestion. Combination of these drugs may lead to comma and sometimes death.
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