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ToolsCompareThymulin vs Tripeptide-29

Thymulin vs Tripeptide-29

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

Immune Support
Thymulin
Skin & CosmeticAnti-Aging & Longevity
Tripeptide-29
Summary
Thymulin is a nonapeptide hormone produced exclusively by the thymic epithelium. It requires zinc for biological activity and plays a critical role in T-lymphocyte maturation, differentiation, and immune regulation. Thymulin levels decline dramatically with age, contributing to immunosenescence.
Tripeptide-29 is a pro-collagen cosmetic peptide composed of proline, hydroxyproline, and glycine — the core repeating unit of collagen. Applied topically, it signals dermal fibroblasts that collagen degradation has occurred, triggering compensatory new collagen synthesis.
Half-Life
~30 minutes active half-life
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
20-30 mcg
0.01-0.1% in formulation
Frequency
10 days per month (Khavinson protocol)
Once or twice daily
Key Benefits
  • Enhances T-cell maturation and differentiation
  • Boosts NK cell cytotoxic activity
  • Reduces inflammatory cytokine production (TNF-α, IL-1)
  • Anti-nociceptive (pain-reducing) properties
  • Restores age-related immune decline
  • Anti-inflammatory via serotonin pathway modulation
  • Stimulates fibroblast collagen synthesis via damage-signal mechanism
  • Reduces fine lines and improves skin smoothness
  • Supports dermal matrix integrity
  • Naturally bioidentical to collagen fragment sequences
  • Well-tolerated in all skin types
  • Synergistic with copper peptides and retinoids
Side Effects
  • Injection site reactions
  • Mild fatigue initially as immune system activates
  • Excellent tolerability profile
  • No documented significant adverse effects at cosmetic concentrations
  • Rare sensitivity reactions in individuals with peptide allergies
Stacks With