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ToolsCompareThymulin vs Palmitoyl Dipeptide-6

Thymulin vs Palmitoyl Dipeptide-6

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

Immune Support
Thymulin
Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6
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.
Palmitoyl Dipeptide-6 is a synthetic dipeptide (lysine-threonine) with a palmitoyl fatty acid tail, designed to penetrate the skin barrier and stimulate the extracellular matrix components essential for skin firmness. It activates fibronectin and type IV collagen synthesis, improving skin density and firmness particularly in mature or sagging skin.
Half-Life
~30 minutes active half-life
Not applicable (topical)
Admin Route
SubQ
Topical
Research
Typical Dose
20-30 mcg
0.005–0.05% 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
  • Increases skin firmness and density
  • Stimulates fibronectin and collagen IV production
  • Strengthens the dermal-epidermal junction
  • Reduces skin sagging in mature skin
  • Improves skin texture and smoothness
  • Supports extracellular matrix integrity
Side Effects
  • Injection site reactions
  • Mild fatigue initially as immune system activates
  • Generally well-tolerated
  • Rare mild skin irritation in sensitive individuals
  • No known systemic effects at cosmetic concentrations
Stacks With