Six years after suing pharmaceutical firms over the opioid epidemic, plaintiffs lawyers are gearing up to fight the manufacturer of Suboxone, a medication used to treat addiction to prescription painkillers.

Suboxone launched in 2002 as a tablet, but lawyers have filed lawsuits over a sublingual film version that the U.S. Food and Drug Administration approved in 2010. More than a dozen lawsuits say that British-based Indivior Inc. failed to warn that its Suboxone film, which dissolves on the tongue, causes severe dental health problems, such as cracking, erosion and tooth loss.