A class action lawsuit has been filed against drug manufacturer Merck, alleging the company failed to warn consumers its bone drug Fosamax may damage jaw bones.

On May 28, 2007, a Canadian law firm filed the first complaint over the drug in Canada.

Osteonecrosis of the jaw (ONJ), commonly known as “jaw death” or “phossy jaw,” can cause jaw bones to deteriorate and die. It also causes pain, soft-tissue swelling, infection, loosening of teeth, and exposed bone.

Merck has already been sued in United States courts over risks associated with Fosamax, with complaints filed in New York, Florida, and Tennessee. In 2006, at least 19 lawsuits were transferred to a New York judge. Fosamax has not been recalled in the U.S.

In 1995, Fosamax was approved in Canada for treating osteoporosis, but was connected to an increased risk of developing osteonecrosis, or “jaw death.”

Source: Joe Schneider, “Merck sued in Canadian court over Fosamax drug, law firm says,” Bloomberg.com, May 28, 2007; Dan MacDonald, “Drugmaker faces class-action suit over ‘jaw death’ warnings,” The StarPhoenix, May 29, 2007.