Viagra was developed in the United Kingdom. In 1998, the American pharmaceutical company, Pfizer Inc., put the drug on the market. The generic name for Viagra is sildenafil, and Viagra is a brand name.Viagra is used to treat erectile dysfunction (impotence) in men. Another brand of sildenafil is Revatio, which is used to treat pulmonary arterial hypertension and improve exercise capacity in men and women. This page contains specific information for...