P21 vs Leuphasyl

A detailed comparison to help you understand the differences and choose the right peptide for your research goals.

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.

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Leuphasyl

Leuphasyl (Pentapeptide-18) is a cosmetic peptide that reduces muscle tension through a mechanism similar to enkephalins. Often combined with Syn-Ake for enhanced anti-wrinkle effects.

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Side-by-Side Comparison

AspectP21Leuphasyl
MechanismInhibits glycogen synthase kinase-3β (GSK-3β) and activates CREB signaling pathway. This promotes BDNF expression, neurogenesis in the hippocampus, and synaptic plasticity.Mimics enkephalin and binds to enkephalin receptors on muscle cells, reducing acetylcholine release and thereby decreasing muscle contraction intensity.
Typical DosageResearch protocols typically use 1-5mg administered intranasally or subcutaneously. Often used in cycles of 2-4 weeks.Topical: 3-8% concentration in serums. Often used in combination products with other muscle-relaxing peptides.
AdministrationCan be administered intranasally for direct CNS access or subcutaneously. Best used cyclically rather than continuously.Topical application to expression lines. Best results with consistent twice-daily use over 8+ weeks.
Side EffectsLimited data. Reported effects include mild headache, temporary brain fog during initial use, and fatigue.Very well-tolerated topically. No significant adverse effects reported at cosmetic concentrations.
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Key Differences

Unique to P21:

Unique to Leuphasyl:

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