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ToolsCompareAlpha-GPC vs PE-22-28

Alpha-GPC vs PE-22-28

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

Cognitive Enhancement
Alpha-GPC
Cognitive Enhancement
PE-22-28
Summary
Alpha-GPC is the most bioavailable form of choline, readily crossing the blood-brain barrier to rapidly increase acetylcholine levels. It enhances cognitive performance, supports GH secretion, and is used as an essential complement to many nootropic peptides (especially those that increase acetylcholine demand like Noopept and Dihexa).
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
~4–6 hours
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
Oral, SubQ
SubQ, Intranasal
Research
Typical Dose
300–600 mg
200–400 mcg
Frequency
1–2x daily
Once daily
Key Benefits
  • Rapidly raises brain acetylcholine levels
  • Enhances memory formation and recall
  • Prevents headaches from nootropic peptides (choline donor)
  • Stimulates growth hormone secretion (modest)
  • Improves attention and processing speed
  • Neuroprotective in Alzheimer's and cognitive decline
  • Approved in Europe for Alzheimer's therapy
  • Enhances power output in athletes (pre-workout)
  • 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 (paradoxically, from excess acetylcholine at very high doses)
  • Nausea at doses > 1200 mg
  • Dizziness
  • Fatigue at high doses
  • +1 more
  • 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