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ToolsCompareThymosin Alpha-1 vs Decapeptide-12

Thymosin Alpha-1 vs Decapeptide-12

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

Immune SupportAnti-Aging & Longevity
Thymosin Alpha-1
Skin & Cosmetic
Decapeptide-12
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.
Decapeptide-12 is a synthetic 10-amino acid peptide developed for skin brightening and depigmentation. It selectively inhibits tyrosinase activity and downstream melanogenesis pathways, reducing hyperpigmentation, dark spots, and uneven skin tone without the irritation associated with hydroquinone.
Half-Life
2–3 hours
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
0.8–1.6 mg
5 ppm (0.0005%) concentration
Frequency
Twice weekly
Twice daily (AM and PM)
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
  • Reduces hyperpigmentation and dark spots
  • Evens skin tone and improves radiance
  • Inhibits post-inflammatory hyperpigmentation
  • Well-tolerated alternative to hydroquinone
  • Effective for melasma and age spots
  • Non-cytotoxic to melanocytes
Side Effects
  • Injection site irritation
  • Mild flu-like symptoms initially (immune activation)
  • Fatigue (rare)
  • Generally very well-tolerated
  • Rare mild irritation or sensitivity in some skin types
  • Results may take several weeks to become visible
Stacks With