(ABC NEWS) -- It's been 15 years since Viagra took America by storm, quickly securing its place as one of the best-selling prescription drugs of all time.
"Viagra was a game-changer," said Dr. Ryan Terlecki, assistant professor of urology at Wake Forest Baptist Medical Center in Winston-Salem, N.C., recalling the not-so-distant days of injectable drugs and surgical implants for erectile dysfunction. "It totally revolutionized men's sexual health, and men's health overall."
The little blue pill was originally designed to treat pulmonary hypertension -- a disease that causes tightness in the chest and shortness of breath.
"These guys started breathing better, but they said to their doctors, 'You'll never guess what else happened to me,'" Terlecki said.
In the 15 years since, Viagra has been tested in dozens of diseases, proving successful in some of the most dismal.
"Viagra is truly unique in the multitude of applications being explored, especially 15 years out," said Terlecki. "It's one of those things that people wonder if we should be putting it in the water."
Here is a list of 15 "vitamin V" successes, failures and exciting prospects.
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