Legal status by country
Is Neuropeptide Y legal?
Written by Aaron CuhaReviewed Sep 2026
How Neuropeptide Y is classified in the United States, United Kingdom, Australia and Canada, side by side. Each country has its own page with a direct answer, the regulator's approval status and what the classification means in practice.
All four countries, side by side
| Attribute | United States · FDA | United Kingdom · MHRA | Australia · TGA | Canada · Health Canada |
|---|---|---|---|---|
| Status | Not approved | Not approved | Not approved | Not approved |
| Classification | Not a medicine; endogenous signalling molecule | Not a medicine; endogenous signalling molecule | Not a medicine; endogenous signalling molecule | Not a medicine; endogenous signalling molecule |
| Note | NPY is a neuropeptide your own brain and sympathetic nerves make. Unlike most entries in this class, there is no approved medicine acting at its receptors to point to: the largest attempt, the Y5 antagonist MK-0557, completed a 52 week randomised trial in 1,661 patients and was abandoned because the weight loss was not clinically meaningful. | No licensed NPY or NPY receptor medicine. Intranasal NPY has been studied only in a phase 1 trial. | No registered NPY or NPY receptor medicine. | No approved NPY or NPY receptor medicine. |
US FDA status: NPY is an endogenous neuropeptide, not a drug, and there is no approved product containing it. No drug acting at any NPY receptor is approved for obesity or for any other indication. Intranasal NPY has been studied in a phase 1 trial in PTSD.. Reviewed Sep 2026.
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General information current as of Sep 2026, not legal advice. Classifications change; confirm with the regulator or a lawyer for a specific situation. Educational use only. This database summarizes published research. It is not medical advice and contains no dosing protocols or recommendations for personal use. The Longevity Archive has no vendor relationships.