Litigation over the hair loss drug Propecia has picked up momentum with over 400 lawsuits pending in state and federal courts.
The lawsuits against drug maker Merck & Co. allege that the drug causes sexual side effects that persist even after patients stops using the drug. Some of the alleged side effects are loss of libido, erectile dysfunction and infertility.
Propecia (finasteride) is marketed as a prescription drug to treat male pattern baldness. Proscar is the same medication with a different dosage. The warning label mentions sexual side effects but indicates they clear up upon discontinuation of use.
More than 140 lawsuits have been consolidated in multidistrict litigation in the U.S. District Court for the Eastern District of New York. More than 150 cases in state courts in New Jersey have been consolidated.
In April 2012, Merck agreed to change its label to warn that sexual problems may continue even after a patient stops taking the drug.
Plaintiffs have alleged that the company knew about the risk of persistent side effects because its labels in other countries had been changed as early as 2008 to reflect those risks.