The drug Propecia, used to treat hair loss and prostate issues, has been found to cause problems relating to sexual drive. The drug causes testosterone to move into an active state, causing multiple changes throughout the body, notably with sexual function. While the drug company maintains that it does not truly reduce sexual function, many studies have results showing that 1.4 percent of men using the drug have been affected. Additionally, reports show that the affect has not only been measured while taking the drug but upwards of 3.5 years beyond.
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