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ToolsComparePE-22-28 vs Somatropin (HGH)

PE-22-28 vs Somatropin (HGH)

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

Cognitive Enhancement
PE-22-28
Growth Hormone PeptidesAnti-Aging & Longevity
Somatropin (HGH)
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.
Somatropin is recombinant human growth hormone (rhGH), identical in structure to the 191-amino acid pituitary-derived growth hormone. It is FDA-approved for growth hormone deficiency, short stature, and wasting conditions. Off-label, it is widely explored for body composition, anti-aging, and performance enhancement, though significant risks accompany unsupervised use.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
2-3 hours (subcutaneous); 20-30 minutes (intravenous)
Admin Route
SubQ, Intranasal
Subcutaneous, Intramuscular (less common)
Research
Typical Dose
200–400 mcg
0.15-0.3 mg/day (adults); titrated to IGF-1 levels
Frequency
Once daily
Once 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
  • Increases lean muscle mass and reduces body fat (particularly visceral)
  • Restores growth hormone deficiency (FDA-approved)
  • Improves bone mineral density
  • Enhances exercise capacity and recovery
  • Supports skin thickness and collagen synthesis
  • Improves lipid profile in GHD patients
  • Explored for anti-aging and cellular regeneration
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)
  • Fluid retention and edema (common, dose-dependent)
  • Carpal tunnel syndrome
  • Joint and muscle pain
  • Insulin resistance and elevated blood glucose
  • +3 more
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