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P21 vs Epithalon

Side-by-side comparison of key properties, dosing, and research.

Cognitive EnhancementAnti-Aging & Longevity
P21
Anti-Aging & Longevity
Epithalon
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.
Epithalon is a synthetic tetrapeptide developed from the pineal gland extract Epithalamin by Russian scientist Dr. Vladimir Khavinson. It is one of the most researched longevity peptides, known for activating telomerase and extending telomere length — the molecular hallmarks of cellular aging.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
2–4 hours
Admin Route
SubQ, Intranasal
SubQ, Sublingual
Research
Typical Dose
100–500 mcg
5–10 mg total per cycle
Frequency
Once daily
0.5–1 mg 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
  • Activates telomerase enzyme, extending telomere length
  • May slow cellular and biological aging
  • Regulates melatonin production and circadian rhythms
  • Improves sleep quality
  • Powerful antioxidant properties
  • May reduce incidence of age-related diseases
  • Supports immune system function
  • Studied for cancer prevention properties in animal models
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Injection site irritation (mild)
  • Temporary sleep changes during cycle (usually improves)
  • Rare: fatigue
Stacks With