(CNN) -- A study released Tuesday indicates that a drug used to treat male pattern baldness reduces the odds of getting prostate cancer by about 25 percent.

But there's some bad news: The same study seems to show that if a man taking finasteride does get the disease, the drug appears to increase his chance of getting a more aggressive form.

"Finasteride is the first drug found to reduce the risk of prostate cancer," said Dr. Ian Thompson of the University of Texas Health Science Center at San Antonio, the study's lead author. "The drug worked for men at low risk for prostate cancer, as well as those at high risk." Read More