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ToolsCompareHGH Fragment 176-191 vs PE-22-28

HGH Fragment 176-191 vs PE-22-28

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

Fat Loss & Metabolic
HGH Fragment 176-191
Cognitive Enhancement
PE-22-28
Summary
HGH Fragment 176-191 (also known as AOD-9604) is a stabilized, modified fragment of the human growth hormone molecule corresponding to amino acids 176–191 with an addition of a tyrosine residue at the N-terminus. It retains HGH's fat-burning properties without the anabolic, diabetogenic, or IGF-1-stimulating effects.
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
~30 minutes
Relatively short; CNS effects may persist due to neurogenic mechanisms
Admin Route
SubQ
SubQ, Intranasal
Research
Typical Dose
250–500 mcg
200–400 mcg
Frequency
1–3 times daily
Once daily
Key Benefits
  • Selective fat burning without anabolic side effects
  • Reduces visceral and subcutaneous fat
  • No insulin resistance or blood glucose disruption
  • Does not stimulate IGF-1
  • May support cartilage and bone repair (at higher doses)
  • No effect on growth or organ size
  • 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
  • Injection site irritation
  • Temporary lethargy
  • Headache (rare)
  • Nausea (rare)
  • 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