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ToolsCompareTB-500 vs P21

TB-500 vs P21

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

Recovery & Repair
TB-500
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
TB-500 is a synthetic fragment of Thymosin Beta-4, a naturally occurring peptide found in nearly all human and animal cells. It promotes cell migration to injury sites, accelerates tissue regeneration, and reduces chronic inflammation.
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.
Half-Life
2–3 hours
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ, IM
SubQ, Intranasal
Research
Typical Dose
2–2.5 mg
100–500 mcg
Frequency
Twice weekly
Once daily
Key Benefits
  • Enhances muscle tissue regeneration
  • Accelerates healing of wounds and injuries
  • Reduces inflammation and pain
  • Improves flexibility and mobility
  • Promotes new blood vessel formation
  • Supports hair growth and skin health
  • May improve cardiac function after injury
  • Systemic healing effect — works at distance from injection site
  • 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
Side Effects
  • Injection site discomfort
  • Fatigue (rare)
  • Headache (rare)
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With