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ToolsComparePE-22-28 vs Dihexa

PE-22-28 vs Dihexa

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

Cognitive Enhancement
PE-22-28
Cognitive Enhancement
Dihexa
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.
Dihexa is a potent experimental oligopeptide derived from angiotensin IV that dramatically enhances synaptogenesis. Preclinical research shows cognitive enhancement orders of magnitude more potent than BDNF — it is considered one of the most powerful nootropic compounds in research, but has very limited human safety data.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
Unknown (limited pharmacokinetic data)
Admin Route
SubQ, Intranasal
Oral, SubQ, Topical
Research
Typical Dose
200–400 mcg
5–10 mg
Frequency
Once daily
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
  • Dramatically increases synapse formation (potentially 10 million× more potent than BDNF in animal models)
  • Enhances memory and learning
  • May reverse cognitive decline
  • Improves neuroplasticity and executive function
  • Long-lasting cognitive benefits from short courses
  • Potential therapeutic agent for Alzheimer's
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)
  • Headache
  • Irritability
  • Brain fog during washout period
  • Unknown long-term effects (insufficient data)
Stacks With