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ToolsComparePE-22-28 vs AHK-Cu

PE-22-28 vs AHK-Cu

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

Cognitive Enhancement
PE-22-28
Skin & CosmeticAnti-Aging & Longevity
AHK-Cu
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.
AHK-Cu is a copper tripeptide composed of alanine, histidine, and lysine chelated to copper. Distinct from GHK-Cu, AHK-Cu exhibits strong affinity for hair follicle receptors and demonstrates potent hair growth stimulation alongside wound healing and skin regeneration properties.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
Hours (topical, variable by formulation)
Admin Route
SubQ, Intranasal
Topical, Scalp application, Subcutaneous (research)
Research
Typical Dose
200–400 mcg
0.01–0.1% concentration
Frequency
Once daily
Once or twice daily
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
  • Stimulates hair follicle growth and reduces shedding
  • Increases dermal papilla cell proliferation
  • Promotes wound healing and skin regeneration
  • Antioxidant protection via superoxide dismutase activation
  • Improves skin elasticity and firmness
  • Supports collagen and elastin production
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)
  • Generally well-tolerated topically
  • Mild scalp irritation or redness in sensitive individuals
  • Possible temporary hair shedding phase at treatment initiation
  • Copper accumulation with excessive systemic use (rare)
Stacks With