CHICAGO (CBS) — It’s a drug that promises to reverse hair loss for men, but is it worth the risk?

As CBS 2’s Pam Zekman reports, some men say they have been devastated by a side effect of the baldness drug Propecia.

“I feel like my twenties have been taken away from me and it’s not fair,” said one young man who asked for anonymity. “I wouldn’t wish this on anybody.”

He was prescribed Propecia to battle his thinning hair and says sexual side effects started the first day he used the drug.

“I wasn’t able to get an erection or it took me a very long time,” he said. “I can’t maintain an erection now.”

At the time he started taking Propecia the insert said less than 2-percent of the men who took it had “sexual side-effects”, and that those went away when the patients stopped taking the drug. But, it’s been two years since Tom last took Propecia and his problem continues.

“I basically feel like my penis and brain are not connected anymore,” he said.

That’s not surprising, according to a recent study conducted by Dr. Michael Irwig of George Washington University.

“The novel part about this study was that it is the first study to describe persistent sexual dysfunction after stopping the medicine where as previous studies have all reported that there have been reversible sexual side effects.”

Lawsuits have been filed against Merck — the maker of propecia — in both Canada and the U.S.

Attorney Alan Milstein filed one of the cases. “The warnings that came with this drug did not adequately tell the potential users of the drug what to be aware of,” Milstein said.

Rosemary McGeady joined the lawsuit after her son Randy killed himself.

“He hated all the things that the drug had done to him,” said McGeady. “He hoped his family and friends would understand why he didn’t want to live anymore. ”

Dr. Robert Brannigan, of Northwestern Memorial Hospital, says he sees half a dozen patients a year who have told him, “I went on this medication and after that I noticed these changes in my sexual health.”

He says there needs to be a long-term study of Propecia

“It’s always been a question in my mind, was this a lingering drug effect or are their other factors coming into play?” Dr. Brannigan said.

As for the 22 year old young man who asked for anonymity, “I wouldn’t trade my hair for not having or not being able to have sex you know, that’s just kind of a no brainer.”

Merck recently changed the wording on their label to acknowledge reports of sexual dysfunction even after people stop taking the drug.

But, a spokesman for Merck disputes the findings in Dr. Irwig’s study. the spokesman says Propecia passed three clinical trials before the drug was approved and that once men stop taking Propecia the sexual side effects go away.

Merck adds that they will vigorously defend themselves against the pending lawsuits.

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