In
March, the U.S. Food and Drug Administration approved Viagra, the
first pill to treat impotence in men.
Pfizer Inc.'s "erection
enhancer," as one doctor put it, took the country by storm, boosting
the company's stock along with the spirits of many men suffering
from impotence. Even after the initial hype surrounding the drug's
debut had subsided, it was clear that the science of sexual dysfunction
had entered a new era -- one that made it big business.
The
ripples began before FDA approval. "I hereby make the outrageous claim
that Viagra will become the world's biggest drug success story, bigger
than anything that has ever been seen," said David Saks, an analyst
with Gruntal & Co.
More than 3 million prescriptions
were written for Viagra during the first five months after it went
on the market in April.
Viagra is effective for an estimated
seven out of 10 patients. It is the first non-surgical treatment for
impotence that doesn't have to be either injected or inserted directly
into the penis. Unlike mechanical devices, it will not cause an erection
unless a man is sexually stimulated.
The drug enhances the relaxant effect of nitric oxide, a chemical
released during sexual stimulation that increases blood flow to the
penis, leading to an erection.
Many doctors cautioned that Viagra is not a magic pill that can cure
any form of impotence, nor is it candy to be taken lightly. Those
who are on heart disease drugs such as nitroglycerin are warned they
could die if they take Viagra, and some researchers have suggested
than any cardiovascular complaint might put a man at higher risk of
a heart attack if he takes Viagra.
In September, the New England Journal of Medicine published new research
that showed Viagra's side effects can include fatal lung complications.
The consumer group Public Citizen has filed a petition with the FDA
demanding that more warning labels be put on the drug.
But in spite of the risks, Viagra remains a hit, and other pharmaceutical
companies are scrambling to develop competitive products.
In October, three U.S. scientists -- whose work dating back decades
helped lead to the development of Viagra -- won the 1998 Nobel Prize
in medicine. Robert Furchgott, Louis Ignarro and Ferid Murad discovered
that the body uses nitric oxide to regulate blood vessels. Their discovery
also has applications for treating conditions ranging from heart disease
to shock.
