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ToolsCompareMelanotan II vs PEG-MGF

Melanotan II vs PEG-MGF

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

Sexual Health & Libido
Melanotan II
Anabolic & IGF
PEG-MGF
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.
PEG-MGF (Pegylated Mechano Growth Factor) is a modified form of MGF (Mechano Growth Factor) where polyethylene glycol (PEG) chains have been attached to extend its half-life from minutes to days. Native MGF is released locally in muscle in response to mechanical stress and quickly degrades. PEGylation allows systemic administration with sustained circulation, enabling whole-body muscle repair and anabolic signaling rather than the purely local effect of native MGF.
Half-Life
1–2 hours
~3 days (due to PEGylation)
Admin Route
SubQ
SubQ
Research
Typical Dose
0.25–0.5 mg
200–400 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
  • Extended half-life (~3 days) vs native MGF (minutes)
  • Systemic muscle satellite cell activation via subcutaneous injection
  • Promotes muscle fiber repair and hypertrophy throughout the body
  • Enhanced recovery from intense training or muscle injury
  • Synergistic with IGF-1 LR3 and growth hormone peptides
  • Useful in sarcopenia, post-injury recovery, and athletic performance
  • Single injection provides multi-day anabolic signaling
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
  • Water retention and localized swelling
  • Potential hypoglycemia at high doses
  • Theoretical cancer growth risk (growth factor)
  • Injection site reactions
  • +1 more
Stacks With