P21 vs GHK-Cu
Side-by-side comparison of key properties, dosing, and research.
Cognitive EnhancementAnti-Aging & Longevity
P21Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu- 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.
- GHK-Cu is a naturally occurring copper complex that declines with age. It is one of the most studied anti-aging peptides, known for powerful skin rejuvenation, wound healing, and tissue remodeling effects.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- 2–4 hours
- Admin Route
- SubQ, Intranasal
- SubQ, Topical
- Research
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- Typical Dose
- 100–500 mcg
- 1–3 mg
- Frequency
- Once daily
- 3–5 times per week
- 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 wrinkles and fine lines
- Improves skin firmness and elasticity
- Accelerates wound healing
- Reduces inflammation and oxidative damage
- Promotes hair growth and thickness
- Supports collagen and elastin production
- May improve overall skin health and appearance
- Resets aged fibroblast behavior
- Anti-fibrotic — reduces scar tissue formation
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Temporary blue-green discoloration at injection site (from copper — harmless)
- Post-injection sting (brief)
- Skin irritation with topical use (rare)
- Stacks With
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