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ToolsCompareDihexa vs PE-22-28

Dihexa vs PE-22-28

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

Cognitive Enhancement
Dihexa
Cognitive Enhancement
PE-22-28
Summary
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.
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
Unknown (limited pharmacokinetic data)
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
Oral, SubQ, Topical
SubQ, Intranasal
Research
Typical Dose
5–10 mg
200–400 mcg
Frequency
Daily
Once daily
Key Benefits
  • 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
  • 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
  • Headache
  • Irritability
  • Brain fog during washout period
  • Unknown long-term effects (insufficient data)
  • 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