The man's penis is like "the tip of the iceberg" or "the canary in the mines," which serve as an indicator of overall health and the possibility of Erectile Dysfunction.

"We lamented the fact that the men had so much shame about Erectile Dysfunction, how rarely anyone came for medical attention," said Dr. Abraham Morgentaler, an associate clinical professor of urology at Harvard Medical School.

"Penis injections and vacuum pumps were available, but these treatments weren't appealing. Men with medical conditions such as diabetes, prostate cancer, hyper cholesterol, endocrinological and cardiovascular problems weren't able to enjoy sex", Goldstein said. "People who couldn't enjoy intimacy before have been given a second life...." he said. "We have had a better life because of it."

Viagra increases blood flow to the penis, enabling a man to have an erection.

Urologists heard from patients who had tried Viagra made them feel as if they were 20-year-olds again.

Anti Erectile Dysfunction drugs like Viagra have come along since.

"Along with the birth control pill in the '60s, Viagra really changed people, society and medicine," Goldstein said.

"Viagra changed the patient-physician relationship.You can walk in and ask about sexual functions. It was a major taboo at some point."

Dr. Gerald Melchiode, a Texas psychiatrist, agreed that Viagra has helped men open up about their sexual health, but finds the commercials a bit much. "I've never run across men singing about their impotency," he said.

Since the appearance of Viagra on the market, the dialogue about sexual dysfunctions has helped doctors identify other health problems in their patients, doctors say.

"You always hear someone drops dead,"said Dr. Chris Steidle, a urologist who wrote the book "Sex and the Heart." "It's not sudden death if you couldn't get an erection. It's a symptom of a heart condition. You wouldn't ignore a stroke, but you would ignore erectile dysfunction -- it's a significant symptom."

Morgentaler said. "There's now good evidence that shows that men with Erectile Dysfunction who have no other symptoms of anything are at increased risk for heart attacks and strokes," he said.

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