FDA Requests Relevant Info to use NAC as a Dietary Supplement

FDA Requests Relevant Info to use NAC as a Dietary Supplement

On November 24, 2021, The Food and Drug Administration (FDA) sent correspondence to industry requesting information on the past use of N-acetyl-L-cysteine (NAC) in products marketed as dietary supplements.

NAC has been approved by the FDA to treat liver side effects from an overdose of Tylenol (acetaminophen), and to loosen the thick mucus in the lungs of people with cystic fibrosis or chronic obstructive pulmonary disease. Recently, the FDA has been issuing warning letters to companies marketing dietary supplements with NAC that are indicated for the treatment of hangovers. The reason for this is that products containing NAC do not meet the definition of a dietary supplement (since NAC was already categorized as a drug in 1963).

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Earlier this year, the FDA received two citizen petitions asking the agency to reconsider its position on the use of NAC as a dietary supplement.

The Council for Responsible Nutrition (CRN) was pulled into the matter and requested the FDA consider reversing the agency’s position on NAC-containing products (ie. that NAC-containing products can be dietary supplements). In addition, the Natural Products Association (NPA) requested the FDA to either determine that NAC is not excluded from the definition of a dietary supplement or enact legislation to make NAC a lawful dietary supplement under the Federal Food, Drug, and Cosmetic Act

On November 24, the FDA issued responses to both petitions in which they requested additional information from the petitioners and any interested parties. The agency noted that more time is needed to carefully and thoroughly review the complex questions posed in these petitions.

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As such, to help the agency respond to these petitions, the FDA is interested in receiving data and evidence as to the earliest date that NAC was marketed as a dietary supplement or as a food, the safe use of NAC in products marketed as a dietary supplement, and any safety concerns with products containing NAC. The FDA will use the information submitted to the public docket and other applicable information to determine if changes to legislation to make NAC lawful as a dietary supplement is appropriate.

The FDA is asking interested parties to submit any information by January 25, 2022, while the agency continues to evaluate both citizen petitions. The agency will use the information submitted for analysis and provide a final response to both petitioners directly once the review is completed.

Individuals may submit electronic comments or written comments regarding these petitions at any time up until the docket is closed; submissions must be received by January 25, 2022, in order to ensure that the FDA is able to review all information in a timely manner. Submit electronic comments to Regulations.gov.

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