Viagra

Viagra is approved oral treatment for men who have difficulty having and maintaining an erection (impotence). It contains sildenafil citrate
An erection is the result of an increase in blood flow into certain internal areas of the penis. Viagra works by enhancing the effects of one of the chemicals the body normally releases into the penis during sexual arousal. This allows an increase of blood flow into the penis.
One pill is taken an hour before sexual activity. By contrast, other approved nonsurgical treatments for erectile dysfunction must be injected or inserted directly into the penis or involve devices placed around the penis. Unlike other treatments that can cause erections even without sexual stimulation, Viagra allows a more natural sequence to occur — an erection in response to sexual stimulation.

Men who have a decrease in their erectile function are ideal candidates. It is found that Viagra is less effective in men who have diabetes or who have had prostate surgery, compared with groups of men who have erectile dysfunction from other causes.

Viagra is rapidly absorbed after oral dose. The effect of the drug lasts upto 4 hours but the effective response is upto 2 hours.When Viagra is taken with a high fat meal, the rate of effectiveness is reduced

Viagra is available as oral tablets in 25mg, 50mg and 100mg strengths. It is manufactured by Pfizer.

Side Effects
The most commonly reported side effects are - headache, flushing, stomach ache, urinary tract infection, diarrhea, dizziness, rash, and mild and temporary visual changes (color perception changes, light perception changes, and blurred vision).
It is reportd that some 69 Americans taking the impotence pill Viagra died. Two patients had strokes, and 46 had cardiovascular events (21 with definite or suspected myocardial infarction, 17 with cardiac arrest, 4 with cardiac symptoms, 3 with coronary artery disease, and one with severe hypotension leading to cardiac arrest).

Viagra is not recommended for people taking commonly prescribed nitrates for cardiac problems because the combination may lower blood pressure. It should be avoided in patients with cardiac problems and should always be taken under medical supervision.

Prolonged erection greater than 4 hours and priapism (painful erections greater than 6 hours in duration) have been reported occationally. In the event of an erection that persists longer than 4 hours, the patient should seek immediate medical assistance. If priapism is not treated immediately, penile tissue damage and permanent loss of potency could result. Patients who are suffering from sickle cell anaemia, multiple myeloma or leukaemia are prone to priapism.