Hydroquinone and the FDA—The Debate?

February 2007 | Volume 6 | Issue 2 | Editorials | 122 | Copyright © February 2007

Melanie D. Palm, Ella L. Toombs

Recently you may have received e-mails, telephone calls, letters or read articles stating that within the next few months, hydroquinone - our workhorse bleaching cream - will be banned in the US.  Point of clarification, on August 29, 2006 the US Food and Drug Administration (FDA) published a monogragh in the United States Federal Register proposing that all hydroquinone products, which have not approved through the New Drug Application process, will be considered misbranded and therefore banned.  This "proposed rule" allowed anyone to submit comments to the FDA by a specified date (in this case December 27, 2006 - later extended 30 days) before the "final rule is published. Once the final rule is published in the Federal Register, manufacturers will have 30 days to remove noncompliant hydroquinone products from the marketplace or risk seizure, fines and possibly imprisonment.  

The following is the history behind the proposed ban. Priot to 1962, the year Congress passed the Kefauver Harris Amendment, drugs sold over the counter (OTC) were assumedto be not only safe but also effective.  The congressional amendment granted the FDA authority to review the entire OTC drug market - thousands of products.  As a result of the review spanning over 40 years, hydroquinone was one of the many products receiving the "GRASE" (generally recognized as safe and effective) designation.  In the 1980s, reports of exogenous ochronosis secondary to hydroquinone use by South African Blacks appeared in the medical literature.  A large proportion of these reports describe subjects that had applied high concentrations (6%-8.5%) of hydroquinone-containing products (hydroalcoholic solutions, some with mercury and/or resorcinal) over extensive body surfaces, several times a day, for years and even decades.  The FDA met with US hydroquinone manufacturers; agreements were made to supply the FDA with studies supporting hydroquinone's safety. The FDA states it never received the data.  In the interim, the FDA's National Toxicology Program (NTP) completed a pharmacologic-toxicology profile on hydroquinone. The results were reviewed by both the FDA and its Cancer Assessment Committee, and hydroquinone was classified as having "some evidence of carcinogenicity." 

Wehave received a list of nongovernment-sponsored pharmacology/toxicology studies from the consumer health care industry that were not included in the FDA's proposed rule. They may not have been aware of the their existence when the rule was written. Iti is important to understand that when these animal studies are performed large amounts of the drug product (far exceeding human doses) are administered systemically and dermally in order to obtain worse case scenario information.  To the best of our knowledge, their have been no cases of cancer associated with cutaneous application of hydroquinone.  

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