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Research peptide

What is the P21 peptide (P021)?

P21 explained in plain English: what it is, what the research shows, side effects, legal status and dosage. There is no validated human dose, and this page doesn't invent one. Also called P021, P21 adamantane.

P21 is not approved for human use by the FDA or any other regulator. This page is educational; talk with a qualified healthcare professional before using any substance.

What is the P21 peptide?

The P21 peptide, also written P021, is a small lab-made peptide based on the most active part of CNTF (ciliary neurotrophic factor), a protein that helps brain cells survive. An added chemical group (adamantane) helps it reach the brain and last longer.

It was developed for research on Alzheimer’s disease. It is not related to the natural p21 protein that controls cell division.

What does the P21 peptide do?

In mouse studies, P21 encouraged new brain cells to form in the memory center (hippocampus), raised BDNF, a protein that supports brain cells, and reduced tau changes linked to Alzheimer’s disease.

What does the research on the P21 peptide show?

The research is in mice and cells. In Alzheimer’s model mice and aged rats, it improved memory tests and protected connections between brain cells.

There are no human trials, so its effects on memory or Alzheimer’s in people are unknown.

P21 peptide side effects and risks

Its side effects in people are unknown. Products sold online aren’t checked for purity, strength or identity.

The P21 peptide is not approved for human use by the FDA or any other regulator.

P21 dosage

The P21 peptide has only been tested in animals, so there is no validated human dose.

There is no approved or validated human dose. This site does not repeat doses from forums, sellers or animal studies.

Medical disclaimer: this dosage information is for education only and comes from the source shown for each row. It is not medical advice and not a recommendation for you. Only a licensed prescriber who knows your health can decide whether P21 is right for you and at what dose. Don't start, change or stop a medicine based on this page, and don't use research peptides or unapproved drugs based on trial doses.

Frequently asked questions

Is the P21 peptide related to the p21 protein?

No. The p21 protein is a natural cell-cycle regulator; the P21 (P021) peptide is a lab-made compound based on a growth factor called CNTF. They just share a name.

Has P21 been tested in people?

No. All published research is in cells and animals, mainly mouse models of Alzheimer's disease.

How is P21 taken?

In mouse studies it was usually given by mouth in food. Sellers offer it in several forms; none is approved.

Sources

  1. Alzheimer's Drug Discovery Foundation (2025), P021 Cognitive Vitality report
  2. Baazaoui & Iqbal (2017), Prevention of dendritic and synaptic deficits with a neurotrophic compound

Last updated .

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