New — Free Peptide Starter Guide (2026): 13 chapters, 34 cited studies

Get it free
ToolsComparePE-22-28 vs IGF-1 LR3

PE-22-28 vs IGF-1 LR3

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

Cognitive Enhancement
PE-22-28
Anabolic & IGF
IGF-1 LR3
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.
IGF-1 LR3 is a synthetic analog of Insulin-like Growth Factor-1 with an extended half-life. It is one of the most potent anabolic peptides available, directly stimulating muscle cell hyperplasia and hypertrophy, and is the downstream mediator of many of GH's anabolic effects.
Half-Life
Relatively short; CNS effects may persist due to neurogenic mechanisms
20–30 hours
Admin Route
SubQ, Intranasal
SubQ, IM
Research
Typical Dose
200–400 mcg
40–80 mcg
Frequency
Once daily
Once daily or split twice 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
  • Direct muscle hypertrophy via IGF-1R stimulation
  • Muscle hyperplasia (new fiber formation) — unique among peptides
  • Rapid gains in lean muscle mass
  • Accelerated recovery from training and injury
  • Increased nutrient uptake by muscle cells
  • Fat oxidation enhancement
  • Bone density improvement
  • Cartilage and connective tissue repair
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)
  • Hypoglycemia (significant risk — insulin-like activity)
  • Acromegaly-like effects with excessive long-term use
  • Jaw and hand swelling
  • Organ hypertrophy with extreme doses
  • +2 more
Stacks With