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ToolsCompareMelanotan II vs Nonapeptide-1

Melanotan II vs Nonapeptide-1

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

Sexual Health & Libido
Melanotan II
Skin & Cosmetic
Nonapeptide-1
Summary
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.
Nonapeptide-1 is a synthetic 9-amino acid peptide that inhibits melanin production by blocking α-MSH (alpha-melanocyte stimulating hormone) receptor binding. Used in cosmetic formulations for skin lightening and evening skin tone, it is particularly effective for UV-induced and hormonal hyperpigmentation.
Half-Life
1–2 hours
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
0.25–0.5 mg
0.05–0.5% concentration in formulation
Frequency
Once daily
Twice daily
Key Benefits
  • 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
  • Inhibits UV-induced tanning and hyperpigmentation
  • Reduces hormonal melasma
  • Evens skin tone at receptor level
  • Well-tolerated with minimal irritation
  • Complementary to tyrosinase inhibitors for enhanced brightening
  • Reduces post-inflammatory hyperpigmentation
Side Effects
  • Nausea (very common, especially in first days)
  • Facial flushing
  • Spontaneous erections in men
  • Darkening or changes in existing moles (monitor closely)
  • +3 more
  • Generally very well-tolerated
  • Rare contact sensitivity in susceptible individuals
  • Theoretical risk of excessive depigmentation with prolonged high-concentration use
Stacks With