Consumer Tooth Whiteners Belong In Homes; FDA Denies ADA Petition For Drug Status

The American Dental Association’s 2009 petition does not support a drug designation for peroxide-containing tooth-whitening products, FDA responds. Further information is needed on formulations, mechanisms of action and safety profiles for FDA to determine whether the products meet the definition of a drug.

FDA says the American Dental Association provided insufficient information to classify peroxide-containing tooth whiteners as drugs available only through dental professionals.

The agency’s response to a citizen petition ADA submitted November 2009 should be welcomed by manufacturers of peroxide-based tooth-whitening products designed for use by consumers at home, including Crest 3D White Whitestrips marketer Procter & Gamble Co.and Colgate-Palmolive Co., which offers whitening toothpaste, mouthwash and related products under its ColgateOptic White brand.

In an April 22 response to the citizen petition, FDA maintains that more information is needed for the agency to consider a drug designation for tooth-whitening preparations that act by chemical means to lighten tooth color.

Specifically, ADA or other stakeholders would have to clarify “which ingredients and which concentrations of peroxide-containing tooth whiteners may affect the structure or function of the body and/or the intended uses of such products,” according to the letter addressed to ADA President Charles Norman and Executive Director Kathleen O’Loughlin.

Without information suggesting otherwise, FDA says it believes most peroxide-containing tooth whiteners meet the definition of a cosmetic under the Food, Drug & Cosmetic Act and the products “may be suitable for use without the supervision of a licensed practitioner and used safely,” contrary to concerns ADA raised in its petition.

“There are millions of exposures and a minimal number of complaints have been received,” with the Center for Food Safety and Applied Nutrition’s adverse event reporting system capturing nine incidents related to peroxide-containing tooth whiteners since 1990. – FDA

P&G argued against ADA’s proposed drug classification for commercially available tooth whiteners in an April 2010 letter to FDA, contending the association’s petition was motivated by the financial interests of its members and omitted readily accessible safety data unfavorable to the group’s position (Also see "P&G Defends Tooth Whitening Cosmetic Classification In FDA Letter" - Pink Sheet, 10 May, 2010.).

“Their desired outcome is to restrict direct-to-consumer access to tooth whiteners that offer results comparable to in-office and dentist-dispensed products,” the firm asserted.

Mechanism-Of-Action Data Needed

In its petition, ADA asked FDA to “to review and establish an appropriate regulatory classification” for tooth whiteners containing hydrogen peroxide or carbamide peroxide (Also see "Dental Association Petitions FDA To Evaluate Tooth Whitening Treatments" - Pink Sheet, 30 Nov, 2009.).

The agency’s policy on peroxide-based products that whiten teeth through a bleaching process has been pending for more than two decades. In the early 1990s, FDA issued warning letters to home-use tooth-whitener manufacturers including Den-Mat Holdings LLC, marketer of Rembrandt whitening kits, asserting that their offerings were unapproved new drugs in violation of U.S. food and drug law.

Den-Mat responded by suing the agency, maintaining that its tooth whiteners were cosmetics under the FD&C Act. After FDA’s motion to dismiss the case was denied in U.S. district court, Den-Mat withdrew its complaint and the agency agreed to review new information submitted by Den-Mat and issue a follow-up determination as to the products’ regulatory status.

That decision has yet to come, but FDA’s response to the ADA petition clarifies its current thinking on the subject. The agency views peroxide-containing tooth whiteners generally as products intended to be applied “for cleansing, beautifying, promoting attractiveness or altering the appearance,” which identifies them as cosmetics under the law.

However, the agency notes that from a regulatory standpoint, products can be cosmetics and drugs. Whether products that use peroxide to whiten teeth affect the structure or function of the body, in addition to altering appearance, depends on their mechanism of action, which is not well understood, according to FDA.

FDA also notes that there are different types of tooth staining, extrinsic and intrinsic, and products available to consumers to whiten teeth rely on different active ingredients at different concentrations. More information is needed on these variables for the agency to determine the precise means by which the whitening action occurs, which could have a bearing on the products’ regulatory classification.

“In sum, there is insufficient data to determine whether, as a group, peroxide-containing tooth-whitening preparations that act by chemical means to lighten tooth color meet the definition of a drug,” FDA states, adding that a case-by-case evaluation of products and their specific formulations and mechanisms of action would be required for the agency to come to conclusions regarding their possible classification as drugs.

Safety Concerns Addressed

ADA also suggested that treating peroxide-based tooth whiteners as cosmetics creates a misleading message that they are “innocuous.”

However, while the group said peroxide-containing tooth whiteners can affect filling materials and corrode mucous membrane or skin, potentially causing tissue damage and sensitivity, data ADA submitted failed to convince FDA the products represent significant safety concerns.

The agency cites a peer-reviewed publication provided by ADA that summarized relevant clinical trials and identified no significant adverse events associated with at-home tooth whiteners. The paper concluded peroxide-containing tooth whiteners have a demonstrated history of posing minimal risks to consumers, particularly when used as directed.

ADA’s petition, and existing scientific literature, also is insufficient to substantiate “general, unspecified concern” expressed by NDA about the use of peroxide-based tooth whiteners by children, adolescents and pregnant women, FDA notes.

Further, ADA suggested direct-to-consumer tooth whiteners have the potential to be overused or abused, and that associated adverse events may be underreported due to lack of awareness. But FDA points out a dearth of available evidence on the subject and notes that since 1990, the Center for Food Safety and Applied Nutrition’s Adverse Event Reporting System has captured just nine complaints related to peroxide-containing tooth whiteners.

The agency acknowledges adverse events stemming from cosmetic and nonprescription drug use typically are underreported to FDA, to other regulatory agencies and to manufacturers. “Despite these limitations,” FDA says, “we note that there are millions of exposures and a minimal number of complaints have been received.”

FDA also considered ADA’s concerns regarding potential risks of consumer tooth-whitener use “without the benefit of professional consultation or examination,” and the group’s assertion that dental professionals should be involved.

The agency notes in order for use of peroxide-containing tooth-whitening products to be restricted to dental professionals, they not only must be classified as a drug, but also meet the risk standards established for Rx pharmaceuticals.

FDA agency encourages ADA to publicize information about FDA’s adverse-reporting system to its members “to help improve reporting of any potential safety concerns associated with these products.”