The U.S. Food and Drug Administration (FDA) released a draft guidance this morning stating its intention to exercise enforcement discretion regarding the sale and distribution of products that contain N-acetyl-cysteine (NAC) and are labeled as dietary supplements. The new guidance follows agency consideration of citizen petitions from the Council for Responsible Nutrition and the Natural Products Association (NPA), which both sought a statement from the agency that NAC is not excluded from the definition of “dietary supplement” under section 201(ff)(3)(B) of the Federal Food Drug & Cosmetic Act. The NPA petition also requested an alternative regulatory action by FDA declaring NAC lawful. FDA issued a final response to the petitions on March 31 denying the request to find NAC a lawful dietary supplement, but leaving open the possibility of rulemaking in line with NPA’s second request.

In the guidance, FDA acknowledges that “our initial review has not revealed safety concerns with respect to the use of this ingredient in or as a dietary supplement. In addition, NAC-containing products represented as dietary supplements have been sold in the U.S. for over 30 years, and consumers continue to seek access to such products.” The American Herbal Products Association had submitted multiple comments in support of both citizen petitions, including documentation demonstrating that NAC had been lawfully marketed as an ingredient in conventional foods and in dietary supplements prior to October 15, 1994.

The draft guidance states that FDA is conducting a full safety review of NAC to consider NPA’s rulemaking request. During this period, FDA intends to apply enforcement discretion to NAC-containing products that the agency views as otherwise lawful dietary supplements. The draft guidance emphasizes that the enforcement discretion policy would not apply to NAC-containing products that make drug claims, or which are adulterated or misbranded under the FD&C Act (other than those misbranded only because they contain NAC and are labeled as dietary supplements).

The full draft guidance is available here.