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ToolsCompareGHRP-6 vs PE-22-28

GHRP-6 vs PE-22-28

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

Growth Hormone Peptides
GHRP-6
Cognitive Enhancement
PE-22-28
Summary
GHRP-6 is the original synthetic GH-releasing peptide and a potent ghrelin receptor agonist. It produces strong GH pulses but is notorious for a significant hunger surge 30–45 minutes post-injection. This hunger side effect makes it less preferred than Ipamorelin or GHRP-2 for most protocols but can be useful in patients with appetite deficiency.
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
15–60 minutes
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
SubQ, Intranasal
SubQ, Intranasal
Research
Typical Dose
100–300 mcg
200–400 mcg
Frequency
2–3 times daily
Once daily
Key Benefits
  • Strong GH stimulation
  • Elevated IGF-1
  • Muscle growth and recovery support
  • Potential anti-inflammatory effects at GI level
  • Useful for patients with appetite deficiency or cachexia
  • Enhanced recovery from training
  • 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
  • Intense hunger surge (30–45 min post-injection)
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 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