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ToolsCompareIpamorelin vs P21

Ipamorelin vs P21

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

Growth Hormone Peptides
Ipamorelin
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
Ipamorelin is a selective GHRP (growth hormone releasing peptide) and one of the cleanest GH secretagogues available. It selectively stimulates GH release without significantly raising cortisol, prolactin, or appetite — making it ideal for long-term use and anti-aging protocols.
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 hours
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
100–300 mcg
100–500 mcg
Frequency
Once to twice daily
Once daily
Key Benefits
  • Increases lean muscle mass
  • Enhances fat loss
  • Improves recovery time
  • Strengthens bones and joints
  • Better sleep quality and REM sleep
  • Enhanced skin elasticity
  • Minimal impact on hunger or cortisol
  • No cortisol or prolactin spike
  • Clean GH release suitable for long-term protocols
  • 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 irritation
  • Temporary water retention (mild)
  • Possible hunger increase (milder than GHRP-6)
  • Numbness or tingling in extremities (rare)
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With