history of viagra

Apr 3, 2008 . Viagra, the diamond-shaped pill, was the first oral treatment for impotence (or erectile dysfunction) and changed the lives of millions of . Viagra was not studied in patients who have a history of the following . Development history of Viagra: Originally developed by Pfizer as a drug to help . On March 27, 1998, the U.S. Food and Drug Administration approved VIAGRA. It was the first oral medication for erectile dysfunction (ED). . History of viagra, hmo pays viagra kaiser, viagra price, pfizer viagra. Viagra's History. Who could have guessed that a former Senate Majority leader and presidential candidate would end up pitching an impotence cure on national . The history of Viagra began with a drug called phentolamine. Learn about phentolamine and how it induces erections and how Viagra improves the process. Sildenafil citrate, sold under the names Viagra, Revatio and under various other names, . 1 History; 2 Mechanism of action; 3 Dosage and price . An interactive resource for 14 to 16 year old biology students about developing of Viagra and how it targets enzyme action to treat ED.