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ToolsCompareP21 vs Melanotan II

P21 vs Melanotan II

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Sexual Health & Libido
Melanotan II
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.
Melanotan II is a synthetic analog of alpha-melanocyte-stimulating hormone (α-MSH) that stimulates melanin production (skin tanning), suppresses appetite, and enhances sexual function. It is not FDA-approved and has significant safety concerns including mole changes and cardiovascular effects.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
1–2 hours
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–500 mcg
0.25–0.5 mg
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
  • Promotes skin tanning and melanin production
  • Reduces UV exposure needed to tan
  • Enhances libido and sexual function
  • May suppress appetite
  • Faster, deeper tan development
  • Longer-lasting tan maintenance
  • Potential photoprotective effects
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Nausea (very common, especially in first days)
  • Facial flushing
  • Spontaneous erections in men
  • Darkening or changes in existing moles (monitor closely)
  • +3 more
Stacks With