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ToolsCompareNonapeptide-1 vs PE-22-28

Nonapeptide-1 vs PE-22-28

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

Skin & Cosmetic
Nonapeptide-1
Cognitive Enhancement
PE-22-28
Summary
Nonapeptide-1 is a synthetic 9-amino acid peptide that inhibits melanin production by blocking α-MSH (alpha-melanocyte stimulating hormone) receptor binding. Used in cosmetic formulations for skin lightening and evening skin tone, it is particularly effective for UV-induced and hormonal hyperpigmentation.
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
Not applicable (topical)
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
Topical
SubQ, Intranasal
Research
Typical Dose
0.05–0.5% concentration in formulation
200–400 mcg
Frequency
Twice daily
Once daily
Key Benefits
  • Inhibits UV-induced tanning and hyperpigmentation
  • Reduces hormonal melasma
  • Evens skin tone at receptor level
  • Well-tolerated with minimal irritation
  • Complementary to tyrosinase inhibitors for enhanced brightening
  • Reduces post-inflammatory hyperpigmentation
  • 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 contact sensitivity in susceptible individuals
  • Theoretical risk of excessive depigmentation with prolonged high-concentration use
  • 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