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ToolsCompareThymosin Alpha-1 vs Melanotan II

Thymosin Alpha-1 vs Melanotan II

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

Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Sexual Health & Libido
Melanotan II
Summary
Thymosin Alpha-1 is a naturally occurring 28-amino acid peptide derived from the thymus gland. It is a powerful immune modulator approved in many countries for treating chronic hepatitis B, hepatitis C, and as an adjunct in cancer immunotherapy.
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.
Half-Life
2–3 hours
1–2 hours
Admin Route
SubQ
SubQ
Research
Typical Dose
0.8–1.6 mg
0.25–0.5 mg
Frequency
Twice weekly
Once daily
Key Benefits
  • Enhances T-cell and NK cell activity
  • Supports recovery from viral and bacterial infections
  • May reduce inflammation systemically
  • Supports healthy aging and immune resilience
  • Improves vaccine response
  • Supports liver health
  • May help with chronic fatigue syndrome and post-viral conditions
  • Approved in multiple countries for hepatitis B and C treatment
  • 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
Side Effects
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
  • Nausea (very common, especially in first days)
  • Facial flushing
  • Spontaneous erections in men
  • Darkening or changes in existing moles (monitor closely)
  • +3 more
Stacks With