What is P21 used for in research?

Research on P21 has focused on: Promotes hippocampal neurogenesis; Improves learning and memory; Neuroprotective effects; May enhance focus; Supports brain plasticity; Potential depression treatment.

What is the typical dose of P21?

Typical research doses are 10-20 mg mg, administered daily. Commonly timed: Morning. These are research figures only — not clinical recommendations.

What are the known side effects of P21?

Side effects reported in research include: Headache (uncommon, mild); Mild fatigue or drowsiness (uncommon, mild); Injection site reactions (uncommon, mild); Mood elevation or mild euphoria (uncommon, mild); Vivid dreams or altered sleep patterns (uncommon, mild); Dizziness or lightheadedness (rare, mild); Allergic reaction (rare, serious). Always consult a qualified professional before use.

How is P21 administered?

P21 is typically administered via Subcutaneous or Intranasal.

In the research literature, P21 is described with subcutaneous or intranasal administration. This is research information only, not medical advice.

What is the evidence quality for P21?

P21 carries an evidence grade of D. Grade D — theoretical or very preliminary evidence only.

Cognitive Enhancement / Subcutaneous / Intranasal

P21

Also known as DTHFPIC Dipeptide

P21 is a nootropic peptide derived from CNTF (Ciliary Neurotrophic Factor). It promotes neurogenesis, especially in the hippocampus, and may improve learning and memory.

What is P21 used for? Research has focused on promotes hippocampal neurogenesis; improves learning and memory; neuroprotective effects.

Compare with other peptides studied forcognitive performance,anxiety and mood

Evidence grade DResearch only

P21 injection at a glance

Figures from the published research literature. Research use only.

Dose range: 10-20 mg
Route: Subcutaneous, Intranasal

How often, when, and the dosing notes are in the dosing reference further down.

Work out your units in the free calculator

Beginner basics

Plain-English guide to P21

What it does: P21 helps your brain grow new nerve cells, especially in the memory center of your brain. Researchers study it to see if it can improve how well you learn and remember things, and to protect brain cells from damage.
Typical dose: Researchers typically use 10-20 mg once per day, injected under the skin or sprayed into the nose.
When to inject: Take it in the morning. The benefits build up slowly over 4-8 weeks, so consistency matters more than perfect timing.
Storage: Keep the dry powder in the refrigerator before mixing. After you mix it with liquid, store it in the refrigerator and use it within the timeframe on the label.
Beginner tip: Don't expect overnight results-give it at least 4-6 weeks of daily use before deciding if it's working, since brain changes happen gradually.

Research status

Evidence grade D: Theoretical or in-vitro only, with no meaningful independent human evidence.
Research only: No regulatory approval in any major jurisdiction. Research use only.

Research compound

For research purposes only. Not approved for human use. Not medical advice.

Research areas

Promotes hippocampal neurogenesis
Improves learning and memory
Neuroprotective effects
May enhance focus
Supports brain plasticity
Potential depression treatment

Side effects

Effect	How often	Severity
HeadacheMay occur in the first 1-2 weeks as the peptide crosses the blood-brain barrier. Usually resolves with continued use. Stay well-hydrated and consider taking in the morning with food.	Uncommon	Mild
Mild fatigue or drowsinessSome users report initial fatigue as the brain adapts to increased neurogenic activity. Typically subsides within 2-3 weeks. Ensure adequate sleep and avoid driving if severely affected.	Uncommon	Mild
Injection site reactionsRedness, mild itching, or small bruising at the injection site. Prevent by rotating sites and using proper injection technique. Apply ice if needed.	Uncommon	Mild
Mood elevation or mild euphoriaSome users report improved mood or mild euphoria, likely due to increased hippocampal neurogenesis and BDNF signalling. This is generally considered a positive effect but should be monitored.	Uncommon	Mild
Vivid dreams or altered sleep patternsIncreased neurogenesis and synaptic plasticity may enhance dream vividness or alter sleep architecture. Usually normalises after 2-4 weeks. Maintain consistent sleep hygiene.	Uncommon	Mild
Dizziness or lightheadednessRare reports in early dosing phase. Sit or lie down if experienced. Ensure adequate hydration and food intake before injection.	Rare	Mild
Allergic reactionSigns include rash, swelling of face/throat, difficulty breathing, or severe itching. Seek immediate medical attention. Discontinue use and inform healthcare provider of peptide use.	Rare	Serious

Dosing reference

Dose scale from the research

Starting: 10 mg
Typical: 20 mg
Upper end: 40 mg

P21 dosing reference
Parameter	Value
Dose range	10-20 mg
Frequency, timing and route are for members Sign up free Log in

Research disclaimer. Figures are drawn from published research literature and community logs. They are not clinical recommendations. Consult a qualified professional. Research use only.

Reconstitution guide

Do not use saline or bacteriostatic saline, use only bacteriostatic water for reconstitution
Do not shake the vial vigorously; gentle swirling prevents peptide degradation
Discard immediately if the solution appears cloudy, discolored, or contains visible particles
Use within 30 days of reconstitution when stored at 2-8°C
Do not freeze the reconstituted solution; freezing may denature the peptide
Use the PeptideVolt reconstitution calculator for your exact concentration

Worked example

With 5 mg in the vial, the water you add changes the draw. Mixed with 1 mL that is 5,000 mcg per mL, so on a U-100 syringe 10 mg is 200 units and 40 mg is 800 units. Mixed with 2 mL it is 2,500 mcg per mL, so 10 mg is 400 units and 40 mg is 1600 units.

Work out your exact dose in the free peptide calculator

Storage and stability

Refrigerate after reconstitution

Molecular and pharmacological data

P21 is a synthetic peptide derived from Ciliary Neurotrophic Factor (CNTF) that crosses the blood-brain barrier and promotes neurogenesis, particularly in the hippocampus: the brain region critical for learning and memory formation. It activates neurotrophic signalling pathways that support the survival, growth, and differentiation of neurons, potentially enhancing synaptic plasticity and cognitive function over time.

Pathways and mechanism detail are for members

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Research citations

2 sources

P21 neurogenic peptide
CNTF-derived cognitive enhancers

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Research use only. All content on this page is provided for informational and educational purposes related to scientific research. P21 is not approved for human use by the FDA or any equivalent regulatory body. This is not medical advice. Do not use any substance discussed here for therapeutic, diagnostic, or preventative purposes. Consult a qualified healthcare professional before making any health-related decisions. The Peptide Volt does not endorse the use of any research chemicals. 18+ only.