Viagra is a Food and Drug Administration approved medication for the treatment of erectile dysfunction. The active ingredient is sildenafil citrate, and it is a prescription drug.
Erectile Dysfunction
Erectile dysfunction is the inability to attain or maintain adequate erection for sexual intercourse. The mechanism of an erection is complex, involving interplay of psychological and nervous, hormonal, vascular and muscular components.
Formulation
Sildenafil citrate is a complex molecule barely soluble in water. It is formulated with other inactive ingredients in Viagra as a blue, film-coated, diamond-shaped tablet.
Mode of Action
The active ingredient in Viagra is a phosphodiesterase inhibitor, which acts to increase the levels of the agent cGMP, which is responsible for adequate erection. Viagra, thus, acts indirectly to enhance an erection in the face of adequate arousal.
Precautions
Common side effects are flushing, headaches, indigestion, "blue vision" and stuffy nose. The concomitant use of certain other drugs such as nitrates with Viagra could lead to life-threatening crises. It should never be used more than once a day.
Misconceptions
Erectile dysfunction affects all age groups. But Viagra should be used only after due and thorough evaluation by a physician.
