P21 vs Palmitoyl Dipeptide-6
Side-by-side comparison of key properties, dosing, and research.
Cognitive EnhancementAnti-Aging & Longevity
P21Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6- 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 Dipeptide-6 is a synthetic dipeptide (lysine-threonine) with a palmitoyl fatty acid tail, designed to penetrate the skin barrier and stimulate the extracellular matrix components essential for skin firmness. It activates fibronectin and type IV collagen synthesis, improving skin density and firmness particularly in mature or sagging skin.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- Not applicable (topical)
- Admin Route
- SubQ, Intranasal
- Topical
- Research
- —
- —
- Typical Dose
- 100–500 mcg
- 0.005–0.05% in formulation
- Frequency
- Once daily
- Once or 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
- Increases skin firmness and density
- Stimulates fibronectin and collagen IV production
- Strengthens the dermal-epidermal junction
- Reduces skin sagging in mature skin
- Improves skin texture and smoothness
- Supports extracellular matrix integrity
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Generally well-tolerated
- Rare mild skin irritation in sensitive individuals
- No known systemic effects at cosmetic concentrations
- Stacks With
- —
- —