GHK vs PE-22-28
Side-by-side comparison of key properties, dosing, and research.
- Summary
- GHK is the natural tripeptide (Gly-His-Lys) released from human albumin that activates tissue remodeling, collagen synthesis, and anti-aging gene expression. The copper-free form is the biological signaling molecule; it chelates copper in tissue to form GHK-Cu but also has independent biological activity.
- 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
- Extremely short as free peptide; tissue binding extends local effects
- Relatively short; CNS effects may persist due to neurogenic mechanisms
- Admin Route
- SubQ, Topical, Oral
- SubQ, Intranasal
- Research
- —
- —
- Typical Dose
- 100–500 mcg
- 200–400 mcg
- Frequency
- Daily or 5x per week
- Once daily
- Key Benefits
- Stimulates collagen and extracellular matrix synthesis
- Activates tissue repair gene expression programs
- Anti-aging: reverses 57% of age-related gene changes
- Antioxidant and anti-inflammatory
- Wound healing and skin barrier repair
- Improves skin laxity, texture, and radiance
- Neuroprotective (stimulates NGF, BDNF)
- Anti-fibrotic in liver and lung models
- 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
- Excellent safety profile (naturally occurring peptide)
- Rare: mild injection site reaction (SC)
- No significant adverse effects identified in research
- 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
- —
- —