Jason McCord sued Merck & Co. in Federal Court.
Merck has been sued at least 15 times in the past two years for similar claims, according to the Courthouse News database.
McCord says he was 36 when he was prescribed Propecia, in 2006, and he took it for four years. He says the trade-off wasn't worth it.
"Male pattern hair loss affects 30 percent of men by the age of 30 years and 50 percent of men by the age of 50 years. Men who suffer from hair loss may be perceived as older and less physically and socially attractive," according to the complaint.
"Male pattern hair loss is a common condition thought to be caused by a combination of genetic factors and a hormone called dihydrotestosterone ('DHT').
"DHT is a substance in the body that can shrink hair follicles until a person no longer has hair on top of his head.
"Finasteride is a 5-alpha reductase inhibitor that decreases the conversion of testosterone to DHT, therefore, preventing hair loss.
"Propecia, or finasteride, may produce undesirable side effects to patients who use the prescription drug, including but not limited to, sexual dysfunction and cognitive impairment.
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