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ToolsComparePal-GHK vs PE-22-28

Pal-GHK vs PE-22-28

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

Skin & CosmeticAnti-Aging & Longevity
Pal-GHK
Cognitive Enhancement
PE-22-28
Summary
Pal-GHK is the palmitoylated form of the GHK tripeptide without a copper ion. By conjugating palmitic acid to glycine-histidine-lysine, skin penetration is substantially enhanced, enabling deeper dermal collagen stimulation. It is commonly paired with Pal-GHK-Cu or GHK-Cu in anti-aging formulations.
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.
Half-Life
Extended (lipid depot in stratum corneum)
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
Topical
SubQ, Intranasal
Research
Typical Dose
0.005–0.1% in formulation
200–400 mcg
Frequency
Once or twice daily
Once daily
Key Benefits
  • Stimulates collagen I and III synthesis in dermis
  • Reduces the appearance of fine lines and wrinkles
  • Improves skin elasticity and firmness
  • Inhibits collagenase (MMP-1) to preserve existing collagen
  • Enhances wound healing and skin repair
  • Well-tolerated in anti-aging serums and creams
  • 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
Side Effects
  • Generally very well-tolerated
  • Rare skin irritation at very high concentrations
  • Possible formulation-dependent comedogenicity
  • Generally well tolerated in animal models
  • Limited human data available
  • Possible mild headache or transient mood changes at initiation
  • Injection site reactions (SC)
Stacks With