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ToolsCompareMelanotan 1 vs P21

Melanotan 1 vs P21

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

Skin & CosmeticSexual Health & Libido
Melanotan 1
Cognitive EnhancementAnti-Aging & Longevity
P21
Summary
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.
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
~40–60 minutes (free peptide); implant formulation (SCENESSE) releases over months
Not well characterized; likely short, but neurogenic effects persist long after administration
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
0.5–1 mg
100–500 mcg
Frequency
Daily until desired color achieved, then maintenance
Once daily
Key Benefits
  • 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
  • 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
  • Nausea (especially at higher doses)
  • Facial flushing
  • Fatigue
  • Injection site reactions
  • +3 more
  • Generally well tolerated in animal studies
  • Limited human clinical data
  • Injection site reactions
  • Potential mild fatigue at initiation
Stacks With