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ToolsCompareP21 vs Melanotan 1

P21 vs Melanotan 1

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

Cognitive EnhancementAnti-Aging & Longevity
P21
Skin & CosmeticSexual Health & Libido
Melanotan 1
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 1 (Afamelanotide) is a synthetic analog of α-MSH that selectively stimulates melanogenesis (tanning) through MC1R activation. It provides UV-independent skin pigmentation and is FDA/EMA-approved under the name SCENESSE for erythropoietic protoporphyria (EPP) and vitiligo.
Half-Life
Not well characterized; likely short, but neurogenic effects persist long after administration
~40–60 minutes (free peptide); implant formulation (SCENESSE) releases over months
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
100–500 mcg
0.5–1 mg
Frequency
Once daily
Daily until desired color achieved, then maintenance
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
  • Induces skin pigmentation/tanning without UV exposure
  • Provides photoprotection in photosensitivity conditions (EPP)
  • FDA-approved for erythropoietic protoporphyria (SCENESSE)
  • Approved in EU for EPP treatment
  • Anti-inflammatory via MC1R
  • Mild libido enhancement
  • Potential skin cancer prevention through melanin protection
Side Effects
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
  • Nausea (especially at higher doses)
  • Facial flushing
  • Fatigue
  • Injection site reactions
  • +3 more
Stacks With