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Tools›Compare›P21 vs Cortagen

P21 vs Cortagen

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Anti-Aging & LongevityRecovery & Repair
Cortagen
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.
Cortagen is a synthetic tetrapeptide (Ala-Glu-Asp-Pro) developed at the St. Petersburg Institute of Bioregulation as a cardioprotective and vascular bioregulator. It stimulates repair of cardiac and vascular tissue, with demonstrated benefits for coronary artery disease, atherosclerosis, and cardiac aging.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
Short peptide half-life; gene regulatory effects persist beyond peptide clearance
Admin Route
SubQ, Intranasal
SubQ, IM, Oral
Research
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Typical Dose
100–500 mcg
10 mg SC or IM daily
Frequency
Once daily
Once 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
  • Cardioprotective — protects cardiac tissue from ischemic damage
  • Promotes cardiac regeneration and repair
  • Improves vascular endothelium function
  • Reduces atherosclerosis progression
  • Anti-aging effect on heart muscle cells
  • Improves cardiac output and exercise capacity
  • Reduces oxidative stress in cardiovascular tissue
  • May reduce arrhythmia frequency
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Excellent safety profile
  • Mild injection site reactions
  • Rare: transient hypotension
  • Rare: mild arrhythmia at initiation in cardiac patients
Stacks With
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