LOUISVILLE, Ky. (WDRB) -- You may have seen ads from a Louisville clinic called Body Shapes, singing the praises of testosterone therapy. One features a man saying, "I get up in the morning and I'm ready to go, I'm zippity do-dah." In another, a muscular man says "I'm stronger, I'm faster, I've got more passion, more energy, and I'm happier than ever."

Dr. Elizabeth Bates was an internal specialist for 13 years. She says she left traditional medicine to work for Body Shapes after discovering that testosterone therapy could do what medications could not do -- including a boost in the bedroom. 

"It definitely improves sexual performance and interest, it improves mental clarity. Many people who have foggy brains will find that's lifted once their on testosterone.  It definitely improves mood. Many times we're able to actually pull people off their anti-depressants, because their mood is so improved," she said.

And Bates says more than 95 percent of patients see not just a small improvement, but a complete life changing transformation. She even says testosterone can do what Cialis and Viagra can't. 

"Testosterone is what drives sex drive, erections. So, if you get that level up and again replenish what is missing, people perform wonderfully."

Treatments come in three forms: a cream that needs to be applied twice a day; pellets that are implanted and last about three months; and shots that have to be given once a week.

Hopes of a new "shot" at youth have propelled testosterone therapy into a multi-billion dollar industry, with the number of patients growing by ten times in the last decade. 

But, endocrinologist Stephen Winters, with University of Louisville physicians, says the effects of testosterone therapy can vary widely.

As far as claims of helping with erectile dysfunction, Winters says, "Very little. Really, drugs like Viagra and Cialis are much more effective treatments of erectile dysfunction. But, they're expensive."  

But, there are concerns that testosterone could actually hurt you. There are questions about whether it could increase the likelihood of prostate cancer. And, a recent study published in the Journal of the American Medical Association shows that men who had t-therapy were more likely to have heart problems. 

Dr. Bates says that study has caused Body Shapes to change its policy, even though it already extensively tested and monitored its patients before.

"So, if somebody comes in with heart disease, because of this data we'll say to them, 'Maybe you're not a great candidate for testosterone.'" 

Cardiologist Andrew DeFilippis with U of L physicians says, though, the studies have fallen short of proving a direct link between testosterone and heart problems.

"There may have been something that led to those patients taking the testosterone therapy as opposed to those who didn't. And, whatever that something was may have been what predisposed them to having the cardiac event, as opposed to the therapy themselves," DeFilippis said.

Still, the studies have sparked a barrage of ads from law firms seeking potential plaintiffs.  

Louisville attorney Kevin Adams says he has about 20 testosterone clients from across the country so far, however none from Kentuckiana. He says the goal is to get drug companies to put better warnings on their products. 

"They're warning about blood clots, but there's not a warning about the seriousness of the cardiovascular risks that we're seeing across the country."

And, Dr. Bates says, until more is known about the negative side of testosterone, she's not taking any chances. 

"If we can give everybody testosterone, it's life-changing for people. But, we have to do it safely," Bates said.

Testosterone levels generally beginning dropping when men are in their late 20s and early 30s.

Typically, it falls by about one percent a year, but Dr. Bates says she's seen men with what she calls "rock bottom" levels in their 40s.

So, how much will the therapy set you back?  The medication and other charges come to about $300 per month.

Dr. Bates says coverage by insurance companies has ranged from none to about 40-percent.

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