Consumer group warns against use of denture adhesives containing zinc

“Because of inadequate or non-existent warnings, the zinc poisoning from denture creams has the potential to become a major public health disaster,” reported US Drug Watchdog, in a statement issued on 12 October. “Patient advocates have pushed for greater disclosure about zinc hazards related to denture cream, but as of now manufacturers have failed to provide adequate warnings.”

According to the Washington, D.C.-based organization, “exposure to excess zinc can lead to unexplained weakness, numbness, loss of sensation or other nerve symptoms.”

“We are talking about household name denture creams like Super Poligrip, we are talking about potentially incredibly bad side effects, and we need to get the word out to every denture user in the United States,” US Drug Watchdog said. “Approximately 35 million Americans wear dentures, most of whom are elderly. Severe zinc poisoning can lead to neuropathy, a condition that affects the nerves. Symptoms of neuropathy vary, but may include numbness or tingling in the feet, legs, hands, and/or arms; a reduction in strength or ability to move legs or feet, or arms and hands; unexplained pain in the extremities; a tendency to stumble or fall down; instability and lack of balance; or a change or decrease in walking stride.”

Manufacturers maintain that the products are harmless when used according to directions.

“Zinc-containing denture adhesive products are safe and effective when used according to the labeled directions,” said Elizabeth Funderburk, spokesperson for the Consumer Healthcare Products Association (CHPA), a Washington, D.C.-based, not-for-profit association representing the makers of over-the-counter medicines and nutritional supplements and the consumers who rely on these healthcare products.

“Zinc-containing denture adhesives made by CHPA member companies have explicit label directions to both explain in words — and demonstrate in pictures — the appropriate use of the creams,” Funderburk said. “In all cases, consumers are advised to use a small amount on well-fitting denture appliances. Too much product is being used if oozing occurs when dentures are put in place.”

A statement from Procter & Gamble, manufacturer of Fixodent, reads, “All Fixodent products undergo rigorous scientific evaluations and safety testing. We continually monitor the safety of our products once in market. We are not aware of any case where denture cream has been definitively linked to a health effect from zinc.

“Fixodent contains ingredients that are generally recognized as safe in the amounts used. All Fixodent products are made, packaged and labeled in accord with FDA manufacturing practices.

“Still, we are doing all we can to make sure our consumers know how to use Fixodent properly. Furthermore, we are monitoring and updating our Web site, our packaging, and our communication to dental professionals when necessary. Our Web site has been updated, and our packaging will soon provide detailed information to our consumers.”

A number of lawsuits have been filed against Procter & Gamble and GlaxoSmithKline, manufacturer of Super Poligrip, on behalf of consumers who claim to have suffered negative health consequences as the result of zinc poisoning resulting from use of the products.

Consumer law firm Parker Waichman Alonso filed a federal lawsuit in the US District Court of the Eastern District of Tennessee related to Super Poligrip (Case#09-cv-22670). Additional lawsuits have been filed against the manufacturers of Fixodent and Super PoliGrip on behalf of individuals who have suffered neuropathy and other serious injuries from denture cream poisoning.

Many of the lawsuits have been consolidated. On 9 June, the U.S. Judicial Panel on Multidistrict Litigation consolidated 12 cases, including two Fixodent cases and 10 Super Poligrip cases, into a multidistrict litigation (MDL) for coordinated pretrial litigation in the U.S. District Court for the Southern District of Florida, according to AboutLawsuits.com, a Web site offering information about personal injury litigation.

AboutLawsuits.com reported that the lawsuits involve similar allegations that the manufacturers failed to warn that high amounts of zinc are contained in the denture adhesive creams, which can be absorbed by the body when a large amount of the product is used or if it is used over a long period of time. Increased levels of zinc in the body can also deplete copper levels, causing a condition known as hypocupremia, which is known to increase the risk of significant neurological problems that can leave users with permanent and debilitating physical injuries.

Although the recommended daily allowance of zinc is 11 mg for men and 8 mg for women, with 40 mg being the maximum amount of zinc that can be safely tolerated, some denture creams have been found to expose users to levels as high as 330 mg per day, AboutLawsuits.com reported.

According to the CHPA, denture adhesives containing zinc are safe when used properly.

“First cleared for marketing in the United States by FDA roughly 15 years ago, these products are very safe when used as directed, and adverse events are extremely rare,” Funderburk said.

The statement from Procter & Gamble reads, “A small amount of zinc is used in Fixodent to help the denture stay in place securely so our consumers can eat, chew and talk more confidently. Zinc is a common ingredient in many over-the-counter products, a variety of foods and is a vital part of our daily diet. In fact, zinc supplements are commonly sold.

“Fixodent users may ingest a small amount of the product. However, we estimate the amount of zinc a consumer would ingest from daily usage of Fixodent is less than the amount of zinc in most daily multi-vitamins and comparable to six ounces of ground beef.”