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ToolsComparePalmitoyl Dipeptide-6 vs Thymulin

Palmitoyl Dipeptide-6 vs Thymulin

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

Skin & CosmeticAnti-Aging & Longevity
Palmitoyl Dipeptide-6
Immune Support
Thymulin
Summary
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.
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.
Half-Life
Not applicable (topical)
~30 minutes active half-life
Admin Route
Topical
SubQ
Research
Typical Dose
0.005–0.05% in formulation
20-30 mcg
Frequency
Once or twice daily
10 days per month (Khavinson protocol)
Key Benefits
  • 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
  • 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
Side Effects
  • Generally well-tolerated
  • Rare mild skin irritation in sensitive individuals
  • No known systemic effects at cosmetic concentrations
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With