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ToolsCompareP21 vs Livagen

P21 vs Livagen

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Anti-Aging & Longevity
Livagen
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.
Livagen is a dipeptide bioregulator (Lys-Glu) developed by Professor Vladimir Khavinson, tissue-specific for the liver and thymus. It supports hepatocyte function, promotes liver cell regeneration, and modulates immune function via thymic activity. Research suggests benefits in chronic liver disease, hepatic aging, and immune restoration following liver damage.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
Short (minutes); gene-regulatory effects are sustained
Admin Route
SubQ, Intranasal
SubQ, Oral
Research
Typical Dose
100–500 mcg
10 mg per day
Frequency
Once daily
Daily for 10–30 days
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
  • Supports hepatocyte regeneration and liver tissue repair
  • Normalizes liver cell protein synthesis
  • Immune modulation via thymic activity
  • Potential benefits in chronic hepatitis and liver aging
  • Anti-aging effects on hepatic tissue
  • May support liver recovery after toxic insult or alcohol damage
  • Complementary to NAD+ and glutathione in liver health protocols
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Generally well tolerated
  • Mild injection site reactions
  • No significant hepatotoxic effects reported at standard doses
Stacks With