FDA framework for nonprescription drugs with approved additional conditions needed for appropriate self-selection or actual use when labeling alone is insufficient.

Definition

An ACNU is one or more FDA-approved conditions an applicant must implement to ensure appropriate self-selection or actual use, or both, without supervision of a licensed practitioner, when labeling alone is insufficient. The final rule became effective May 27, 2025. Key provisions are 21 CFR 314.56 and 201.67, with additional related drug reporting requirements. Initial approval requires a separate application, not a supplement to an existing approved application. An ACNU tool is not automatically a medical device or a combination product; assess its actual functions and intended use separately.

Why it matters

Common pitfalls

•Do not assume an ACNU app is either marketing software or a medical device without evaluating its functions and intended use.
•Failing to integrate human factors testing of the ACNU early, FDA expects evidence the additional condition actually achieves safe self-selection.
•Ignoring post-market obligations, manufacturers must monitor whether the ACNU continues to function as intended in real-world use.

Sources

FDA ACNU Final Rule (Dec 2024) · Federal Register
21 CFR 201.67, ACNU labeling requirements · eCFR
European Commission - Medical Devices · European Commission
FDA ACNU final rule and effective date · FDA
FDA seven things about ACNU · FDA

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