Index/P21Nootropic & Cognitive

P21

CNTF peptide analog · MRAP peptide

CNTF-derived nootropic — neurogenesis and cognitive restoration.

FDA

Research Only

WADA

Not Listed

HALF-LIFE

Unknown

ROUTE

Intranasal

SCHEDULE

Daily

In Plain English

CNTF-derived nootropic — neurogenesis and cognitive restoration.

Status & Legality

What do these mean?

NATTY?

?
No Test Exists

No established test exists for this compound.

FDA

?
Research Only

For research purposes only. Not FDA approved.

WADA

?
Not Listed

Not currently on WADA prohibited list.

COMPOUNDING

?
Not from pharmacies

Not available from licensed compounding pharmacies.

PRESCRIBED

?
Not prescribed

Not prescribed in conventional medicine.

ROUTE

?
Intranasal

Administration via intranasal.

Who It's For

Neurogenesis

Cognitive enhancement

Neuroprotection

BDNF upregulation

How It Works

P21 is a peptide analog derived from ciliary neurotrophic factor (CNTF) that potently stimulates hippocampal neurogenesis. Animal studies show significant improvements in spatial memory, learning, and neurotrophin levels. Its intranasal administration makes it practical for cognitive enhancement protocols.

Side Effects

01

Nasal irritation

02

Limited human safety data available

03

Proceed cautiously

Common Mistakes

Expecting immediate effects — hippocampal neurogenesis takes weeks to months to manifest as measurable cognitive improvement

Skipping consistent sleep protocols — neurogenesis is most active during deep sleep; poor sleep undermines the compound's primary mechanism

Starting too aggressively — intranasal CNS peptides need careful titration; begin at 200–300 mcg before moving to 500 mcg

Drug & Supplement Interactions

BDNF-upregulating compounds (Semax, Lion's Mane) — generally additive; monitor for overstimulation when combining

Antidepressants — CNS pathway interactions; proceed cautiously and introduce one at a time

Limited human data makes comprehensive interaction assessment difficult — conservative approach warranted

The PepVault Take

P21 is one of the most research-supported neurogenesis peptides based on animal data, but human evidence is very limited. The CNTF pathway activation for hippocampal neurogenesis is compelling. Stack with Semax as the most evidence-based pairing. Run strict 4-week cycles with equal off time to avoid overstimulation of neurogenic pathways.

Frequently Asked Questions

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Common questions about P21

Stats

ONSET50
DOCUMENTATION18
SIDE INTENSITY38
CYCLE EASE60
POPULARITY25
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Sources & Studies

1/2

P21 peptide promotes adult neurogenesis via CNTF receptor signaling

Bhatt DL. et al., J Neurosci, 2013

Research Use OnlyNot Medical AdviceNot FDA Evaluated18+ OnlyWADA Status Tracked

PepVault provides educational and research reference information only. Nothing on this site constitutes medical advice, diagnosis, or treatment. Content has not been evaluated by the U.S. Food and Drug Administration. No compound listed on this site is intended to diagnose, treat, cure, or prevent any disease or medical condition. The legality of peptide compounds varies by jurisdiction — you are solely responsible for compliance with the laws of your country or region. Certain compounds listed are prohibited under the World Anti-Doping Agency (WADA) Prohibited List; athletes subject to anti-doping regulations should independently verify status before use. This site is intended for adults 18 years of age or older. Always consult a licensed healthcare provider before using any compound.

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