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ToolsComparePE-22-28 vs Thymulin

PE-22-28 vs Thymulin

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

Cognitive Enhancement
PE-22-28
Immune Support
Thymulin
Summary
PE-22-28 is a synthetic analog of spadin derived from sortilin, designed to block TREK-1 potassium channels with rapid-onset antidepressant and neurogenic effects. It shows fast-acting depression relief (within 24 hours) and promotes hippocampal neurogenesis.
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
Relatively short; CNS effects may persist due to neurogenic mechanisms
~30 minutes active half-life
Admin Route
SubQ, Intranasal
SubQ
Research
Typical Dose
200–400 mcg
20-30 mcg
Frequency
Once daily
10 days per month (Khavinson protocol)
Key Benefits
  • Rapid-onset antidepressant effects (within 24 hours)
  • Promotes hippocampal neurogenesis
  • Improves cognitive performance and memory
  • Reduces anxiety and depressive behavior
  • Novel mechanism — does not act on serotonin/dopamine/GABA receptors directly
  • May help treatment-resistant depression
  • Neuroprotective effects
  • 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 in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
  • Injection site reactions
  • Mild fatigue initially as immune system activates
Stacks With