GlaxoSmithKline, the maker of Super PoliGrip denture adhesives, said in a letter to dentists last month that in 2009 it received an increased number of adverse event reports describing the development of neurological symptoms, myeloneuropathy and blood dyscrasias. According to the letter, dated February 18, those reports, together with the published literature, suggest that excessive use of zinc-containing denture creams may lead to the development of excessive levels of zinc in the blood, associated with copper deficiency.
The same day GlaxoSmithKline’s letter was released, the company announced it would voluntarily stop the manufacture, distribution and advertising of Super PoliGrip varieties that contain zinc. Those products – Super PoliGrip â€˜Originalâ€™, â€˜Ultra Freshâ€™ and â€˜Extra Careâ€™ – will be reformulated, with new zinc free varieties expected to be available this spring. In spite of this action, none of these products is being recalled and those currently in stores are still available for sale.
The human body does need zinc â€“ but only in small amounts. Studies show that consuming at least 50 milligrams of zinc a day for a few months could lead to copper deficiency, which can cause anemia, bone loss, nerve damage and other problems. Ingesting 80 or 100 milligrams or more for months or even years can lead to irreversible damage.
Compelling evidence exists that long-term exposure to the zinc in denture cream can lead to nerve damage and disability. In August 2008, the peer reviewed journal â€œNeurologyâ€ reported on four patients suffering from neuropathy and other neurological symptoms typical of zinc poisoning and copper depletion. The article specifically linked excess zinc in denture cream to â€œprofound neurologic diseaseâ€ in the patients reviewed.
This past fall, researchers at Vanderbilt University and the University of Michigan published a study in NeuroToxicology that detailed 11 patients who had suffered from significant injuries and neurological disorders for a period of years. The study authors discovered that all 11 patients had used a zinc-containing denture cream, such as Fixodent or Super PoliGrip, to keep their dentures in place. Blood test confirmed that each suffered from zinc poisoning and copper deficiency.
After the 11 patients stopped using denture creams, their zinc and copper levels normalized. This led the study authors to conclude that: â€œInappropriate use of denture cream appears to be the sole source of excessive zinc in these patient.â€ Sadly, even after they stopped using denture cream, the neurological condition of the 11 patients did not improve, and was seemingly irreversible.
Dozens of people have filed lawsuits claiming excessive exposure to zinc in products like Super PoliGrip caused them to suffer from severe neurological injuries. Last year denture cream lawsuits pending in federal courts were consolidated in a multidistrict litigation in the United States District Court for the Southern District of Florida, Miami Division, before the Honorable Judge Cecilia Altonaga (MDL No. 2051).
Since GlaxoSmithKline made its announcement regarding zinc-containing Super PoliGrip denture creams, <"http://www.yourlawyer.com/">Parker Waichman Alonso LLP, a national law firm involved in the denture cream litigation, has issued several statements calling on GlaxoSmithKline to issue a full recall of all Super PoliGrip products made with zinc. The firm has also appealed to Wal-Mart, Target and other retailers to pull these denture creams from their shelves.
“If these Super PoliGrip denture creams are allowed to remain on store shelves, it is almost certain that more consumers will suffer zinc-related injuries,” Andres Alonso, a partner of Parker Waichman Alonso, said in one statement. “GlaxoSmithKline must issue a full recall right now.”
Last July, Mr. Alonso was named Co- Lead Counsel to the Plaintiffsâ€™ Steering Committee in the Denture Cream Products Liability Litigation by Judge Altonaga.