Florida plaintiff Thomas P. is suing Merck & Co. for the injuries he allegedly suffered from taking their hair loss products, Propecia and Proscar. Thomas claims that as a direct result of these medications, he developed and is still continuing to suffer from sexual dysfunction.

Propecia is sold as a prescription treatment for androgenic alopecia (male-pattern baldness), while Proscar is prescribed to treat benign prostate hyperplasia (prostate enlargement). Both drugs contain the active ingredient finasteride, and are manufactured and sold by Merk & Co. and Merck Sharp & Dohme Corp.

“Finasteride may produce undesirable side effects to patients who use the prescription drug, including but not limited to: sexual dysfunction that continues after discontinuation of treatment, including erectile dysfunction, libido disorders, ejaculation disorders, and orgasm disorders; breast cancer; prostate cancer; and cognitive impairment,” the Propecia lawsuit states.

“The rates of the sexual dysfunction as a result of finasteride are reported to be as high as 39% in published clinical studies. In addition, it has been reported in 2003 that only 50% of patients experience resolution of their sexual function adverse events after discontinuation of finasteride,” the lawsuit continues.

The plaintiff was prescribed and used Propecia and Proscar as directed from 2009 to 2010, during which time he began to suffer from and was diagnosed with sexual dysfunction, the Propecia lawsuit says. He has suffered various libido problems ever since, and is unsure if they will ever go away.

More than 742 Propecia lawsuits alleging similar finasteride side effects are pending trial.

“Defendants knew or should have known that Propecia and Proscar, when taken as prescribed and intended, causes and contributes to an increased risk of persistent and/or permanent serious and dangerous side effects… even after discontinuation of use,” the Propecia lawsuit states.

The plaintiff says he never would have agreed to take Propecia and Proscar if he had known the risk of permanent sexual dysfunction, or any other possible dangers to his quality of life. He is suing Merck for omitting this risk from the products’ labels.

The Propecia lawsuit claims Merck had the civil responsibility to warn consumers of all the risks attached to their products. Patients and doctors alike rely on the accuracy of drug warning labels so they can identify potential complications patients may experience; Merck allegedly failed to do this by omitting the risk of permanent sexual side effects from Propecia and Proscar on its drug warning labels.

The Propecia lawsuit is Case No. 14-cv-5142. It was filed in the Propecia MDL, where more than 742 similar lawsuits have been consolidated, known as In Re: Propecia (Finasteride) Product Liability Litigation, MDL No. 2331, in the U.S. District Court of Eastern New York.

The Propecia MDL was created in April 2012 to more efficiently handle the growing number of complaints from men that finasteride side effects caused them to suffer permanent sexual dysfunction. Plaintiffs contend that Merck knew or should have known that Propecia side effects could be chronic and include erectile dysfunction, reduced libido and other sexual problems.