P21 vs Palmitoyl Tetrapeptide-7
Side-by-side comparison of key properties, dosing, and research.
Cognitive EnhancementAnti-Aging & Longevity
P21Skin & Cosmetic
Palmitoyl Tetrapeptide-7- Summary
- P21 is a synthetic peptide derived from CNTF (ciliary neurotrophic factor) that promotes hippocampal neurogenesis, enhances memory and spatial learning, and may reduce amyloid-beta pathology. It is used as a neurogenic and cognitive enhancer with potential anti-Alzheimer's applications.
- Palmitoyl Tetrapeptide-7 (Rigin) is a cosmetic peptide consisting of palmitic acid linked to the tetrapeptide sequence GQPR (Gly-Gln-Pro-Arg). It was designed to mimic the biological activity of the IgG immunoglobulin C-terminus, which downregulates the production of interleukin-6 (IL-6), a key driver of skin aging and inflammation.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Topical penetration-dependent; effects last hours to days
- Admin Route
- SubQ, Intranasal
- Topical
- Research
- —
- —
- Typical Dose
- 100–500 mcg
- 2-5 ppm concentration in formulation
- Frequency
- Once daily
- Twice daily
- Key Benefits
- Promotes hippocampal neurogenesis
- Enhances spatial memory and learning
- Increases BDNF expression
- Reduces amyloid-beta plaque formation (animal models)
- Anti-tau pathology potential
- Cognitive enhancement without stimulant effects
- Potential therapeutic for Alzheimer's and cognitive aging
- Reduces IL-6 inflammatory cytokine in skin
- Prevents 'inflammaging' of the skin
- Inhibits MMP collagen-degrading enzymes
- Synergistic with Matrixyl for anti-aging
- Clinically tested for wrinkle and skin texture improvement
- Well-tolerated topically
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Contact sensitization (rare)
- Well-tolerated at standard concentrations
- Stacks With
- —
- —