P21 vs TB-500
Side-by-side comparison of key properties, dosing, and research.
- 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.
- 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.
- Half-Life
- Not well characterized; likely short, but neurogenic effects persist long after administration
- 2–3 hours
- Admin Route
- SubQ, Intranasal
- SubQ, IM
- Research
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- Typical Dose
- 100–500 mcg
- 2–2.5 mg
- Frequency
- Once daily
- Twice weekly
- 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
- 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
- Side Effects
- Generally well tolerated in animal studies
- Limited human clinical data
- Injection site reactions
- Potential mild fatigue at initiation
- Injection site discomfort
- Fatigue (rare)
- Headache (rare)
- Stacks With
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