Oral testosterone can lead to liver problems, study co-author McVary said, and testosterone overuse -- such as by some bodybuilders -- can lead to rage, acne, congestive heart failure and worsening of urinary symptoms.
In the new study, the researchers looked at the websites of 70 providers of testosterone supplements in Chicago, Houston, Los Angeles, New York City and Philadelphia. One-third were run by people who weren't physicians.
Only 27 percent described side effects of testosterone supplements, while 95 percent touted benefits. About a third of the sites run by urologists or endocrinologists described male breast growth as a potential risk. Seven percent of all the sites, however, denied breast growth as a potential side effect.
Amory said the new research appears to be valid and reflects "my impression of the way in which this [testosterone] is being oversold to patients."
McVary and Amory said they don't know if the clinics are acting legally when they omit information about testosterone risks. However, the U.S. Food and Drug Administration requires drug companies to describe the risks of prescription medications in their ads.
What to do? When it comes to medical information on the Internet, McVary said, "only go to legitimate sites that are sponsored by a medical organization that is known to you."
The findings were scheduled to be released Tuesday at the American Urological Association annual meeting in San Diego. The data and conclusions should be viewed as preliminary until published in a peer-reviewed journal.
For more about testosterone, try the U.S. National Library of Medicine.
SOURCES: Kevin McVary, M.D., chairman and professor of urology, Southern Illinois University School of Medicine, Springfield; John Amory,
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