> ## Content Index
> Fetch the complete content index at: https://www.fdaweb.com/llms.txt
> Use this file to discover other available public pages before exploring further.

# FDA Mulls Enforcement Discretion on NAC Products
- URL: https://www.fdaweb.com/fda-mulls-enforcement-discretion-on-nac-products/
- Published: 2022-04-01T12:00:00.000Z
- Updated: 2026-09-14T17:39:01.000Z
- Author: David McFarland
- Tags: Drugs, #legacy-id-D5151508

FDA says that it is considering exercising enforcement discretion for N-acetyl-L-cysteine (NAC)-containing products labeled as dietary supplements. But for the time being, the agency says it is still reviewing the issue and it denied two citizen petitions from the [Council for Responsible Nutrition](https://www.regulations.gov/document/FDA-2021-P-0523-0022?ref=fdaweb.com) and the [Natural Products Association (NPA)](https://www.regulations.gov/document/FDA-2021-P-0938-0030?ref=fdaweb.com) that asked it to determine that products containing NAC are not excluded from FDA’s definition of a dietary supplement. The agency says it intends to issue guidance about its policy on NAC-containing products labeled as dietary supplements in the near future.

In a [just-posted letter](https://www.fda.gov/food/cfsan-constituent-updates/fda-issues-response-two-citizen-petitions-nac-dietary-supplements?ref=fdaweb.com) to constituents, FDA says that while its response to the citizen petitions confirmed NAC is excluded from the definition of a dietary supplement, “the agency has not yet reached a decision on the NPA citizen petition’s alternative request that the agency undertake rulemaking to allow the use of NAC in dietary supplements. The FDA continues to review this request.”

The dietary supplement industry reportedly is concerned about recent Warning Letters to several dietary supplement manufacturers marketing them as hangover cures. These letters said NAC is excluded from the definition of a dietary supplement because it was first approved as a drug in 1963\. Some 1,170 products containing NAC were listed in the Dietary Supplement Label Database maintained by the National Institutes of Health.