A New Mexico man has sued drug manufacturer Merck, alleging the pharmaceutical company’s hair-loss drug Propecia (finasteride) leads to dangerous and serious side effects, including sexual dysfunction, which the company failed to adequately warn their consumers against.

Bruce O. began taking Propecia in 1999 to treat male pattern baldness. He continued to take the prescription medication for five years. Before taking Propecia, Bruce had never suffered from sexual dysfunction, but problems began to manifest when he started using Propecia.

Bruce’s Propecia erectile dysfunction continued after he stopped taking the medication and continues to this day, according to the Propecia lawsuit.

What Is Propecia?

The FDA approved Propecia in 1997, in the form of a one-milligram tablet of finasteride, as a cosmetic treatment for male pattern hair loss. More than 1 million people in the United States have used Propecia since it was introduced into the U.S. pharmaceutical market.

Finasteride (Propecia) was initially developed to treat patients with symptoms of benign prostatic hyperplasia (“BPH”), and was later approved for the treatment of androgenic alopecia, also known as male pattern hair loss. 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.

Male pattern hair loss is believed to be the result of inherited genes and a hormone called dihydrotestosterone (DHT), which is a substance in the body that can shrink hair follicles until a person no longer has hair on top of his head.

Propecia Lawsuit

Merck, according to Bruce’s Propecia lawsuit, promoted the drug as a safe treatment for male pattern baldness, with minimal risk. Its label represented that only a limited number of people who take Propecia experience sexual dysfunction side effects such as a decreased libido, erectile dysfunction, and ejaculation disorder.

But the United Kingdom, Sweden, and Italy have all changed the Propecia label to include a warning about persistent and/or permanent erectile dysfunction, even after discontinuing the medication, the Propecia lawsuit claims.

The FDA website shows that Merck has updated the Propecia label in the United States nine times since the drug hit the market, yet none of the label revisions as of June 9, 2011, included a warning regarding persistent and/or permanent sexual dysfunction in patients that discontinued use of the prescription drug, according to Bruce’s Propecia sexual dysfunction lawsuit.

In April 2011, Merck updated Propecia’s prescribing information on the drug’s website to indicate patient reports of “erectile dysfunction that continued after discontinuation of treatment,” the first warning to U.S. patients about the Propecia side effect. However, Bruce alleges the Propecia label in the United States still does not warn users of persistent and/or permanent sexual dysfunction and cognitive impairment after discontinuation of use.

Finasteride may produce undesirable side effects for patients who use the prescription drug, including but not limited to, sexual dysfunction and cognitive impairment. The rates of the sexual dysfunction as a result of finasteride are reported to be as high as 39 percent in published clinical studies. In addition, it was reported in 2003 that only half of patients resolve their sexual dysfunction events after ceasing to take the drug.