P21
P21 is a synthetic peptide derived from Cerebrolysin, specifically designed to mimic the neurotrophic effects of the parent compound. It promotes neurogenesis and has shown cognitive-enhancing properties in research.
Mechanism of Action
Inhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity.
Dosage Overview
Dose Range
1 mg – 5 mg
Route
subcutaneous
Frequency
1x daily
Cycle Length
2–4 weeks
Reconstitution
Typical Dosage (Research)
Research protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks.
Can be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously.
Considerations for Men & Women
Women: CNTF-derived neurogenic peptide. Very limited human data. No established sex-specific differences. Avoid during pregnancy due to neurotropic activity and insufficient safety data.
Men: Same research protocols apply. Limited clinical data for both sexes. Used primarily in neurogenesis research.
Individual responses vary. These notes reflect general trends from research literature and are not medical advice.
Quick Calculator
Quick Calculator
Concentration: 2,500 mcg/ml
Volume to inject: 0.40 ml
Syringe units (U-100): 40.0 units
Pre-filled with P21 defaults. Adjust values as needed.
Side Effects & Risks
Limited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue.
Very limited human research. Long-term effects unknown. Theoretical concerns about effects on cell proliferation pathways.
Who Uses P21
Researchers, advanced nootropic users, those seeking neurogenesis support.
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