

Viagra, a name now that has become known in every household is a patented drug that took the world by storm because of its ability to treat erectile dysfunction in men. This drug was initially studied for its effects on hypertension and angina but was later discovered to be able to treat erectile problems.
Viagra is the brain child of Pfizer and was given a patent in the year 1996 and received authorization from the Food and Drug Administration in the year 1998 to treat erectile dysfunction, a first of its kind. The wonder drug created waves all over the world with annual sales soaring over a billion dollars.
Viagra is the brand name manufactured by Pfizer that also brings out another drug with similar generic composition by name Revatio that is used for the treatment of pulmonary arterial hypertension. The generic composition of Viagra is Sildenafil citrate.
