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ToolsComparePentapeptide-18 vs Melanotan 1

Pentapeptide-18 vs Melanotan 1

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

Skin & CosmeticAnti-Aging & Longevity
Pentapeptide-18
Skin & CosmeticSexual Health & Libido
Melanotan 1
Summary
Pentapeptide-18 (Leuphasyl) is a synthetic pentapeptide that mimics the sequence of enkephalin, an endogenous neuropeptide. It acts on neuronal pain receptors in facial muscles to reduce muscle contraction intensity and depth of expression lines, functioning similarly to Argireline (Acetyl Hexapeptide-3) but via a different receptor mechanism.
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 applicable (topical)
~40–60 minutes (free peptide); implant formulation (SCENESSE) releases over months
Admin Route
Topical
SubQ
Research
Typical Dose
0.005–0.05% in formulation
0.5–1 mg
Frequency
Twice daily
Daily until desired color achieved, then maintenance
Key Benefits
  • Reduces depth of expression lines (forehead, crow's feet, glabellar)
  • Inhibits acetylcholine release for muscle-relaxing effect
  • Complementary mechanism to Argireline for enhanced anti-wrinkle activity
  • Reversible and well-tolerated
  • No risk of systemic paralysis at cosmetic concentrations
  • Suitable for daily use in serums and creams
  • 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 very well-tolerated topically
  • Rare skin sensitivity or mild irritation
  • Theoretical opioid receptor desensitization with very prolonged high-dose use (not documented cosmetically)
  • Nausea (especially at higher doses)
  • Facial flushing
  • Fatigue
  • Injection site reactions
  • +3 more
Stacks With