Is P21 legal in the United States?

A small peptide made from a nerve growth factor. In animals it helped grow new brain cells and protected against Alzheimer-like changes.

P21 is a chain of four amino acids taken from the working part of ciliary neurotrophic factor (CNTF), a protein that helps nerve cells grow. It was built to get into the brain and copy CNTF's effect at a much smaller size.

How it works: It copies CNTF's signal. That helps new brain cells form in the memory center, the hippocampus, and helps connections between brain cells adapt.

Approval history: Not FDA-approved; experimental

Approves prescription drugs, each for a named use. It also acts against unapproved products, including peptides sold online. Compounding pharmacies, which mix drugs to order, may make some compounds with a prescription. That only applies when the FDA puts the compound in a category of bulk ingredients it allows.

The legal category above is how The Longevity Archive reads U.S. Food and Drug Administration listings for P21 on the reviewed date. It is not a legal opinion. Rules change. Bringing a compound into the country, prescribing it and owning it can each be treated differently. Check with the agency before you act on anything here.

Check FDA directly

Whether P21 is banned in sport is set by the World Anti-Doping Code and by military rules, not by its legal status in the United States. Before you compete or get tested, look up P21 by name on the Prohibited List, or look up a named product in Global DRO. Under the World Anti-Doping Code, category S0 bans, at all times, any drug-like substance that meets two tests. No other section of the List covers it. And no government health regulator anywhere has a current approval for it as a treatment in people. Many substances that are approved somewhere are banned by name in another section. So approval does not mean a substance is allowed in sport.

• WADA Prohibited List
• Global DRO (check a named product)
• USADA (US athletes)
• Operation Supplement Safety (US service members)

The rules you compete or serve under decide this, not this page.