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ToolsCompareMelanotan II vs LL-37

Melanotan II vs LL-37

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

Sexual Health & Libido
Melanotan II
Immune SupportRecovery & Repair
LL-37
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.
LL-37 is the only known human cathelicidin antimicrobial peptide. It kills bacteria, fungi, and viruses by disrupting their membranes, while simultaneously modulating immune responses. Used for antimicrobial protection, immune priming, and wound healing.
Half-Life
1–2 hours
Very short (~1–2 hours) in plasma due to protease degradation; topical use bypasses systemic clearance
Admin Route
SubQ
SubQ, Topical, Intranasal
Research
Typical Dose
0.25–0.5 mg
100–300 mcg
Frequency
Once daily
2–3x per week
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
  • Broad-spectrum antimicrobial (bacteria, fungi, viruses)
  • Promotes wound healing and angiogenesis
  • Immune system modulation — enhances innate immunity
  • Reduces LPS-mediated endotoxemia
  • Anti-biofilm activity against resistant organisms
  • Promotes tissue regeneration and keratinocyte migration
  • May protect against sepsis
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
  • Injection site redness and irritation
  • Mild inflammatory response at injection site
  • Potential pro-inflammatory at high doses
  • Rare: fever or flu-like symptoms at initiation
Stacks With