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ToolsCompareGHK vs PGPIPN

GHK vs PGPIPN

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

Skin & CosmeticAnti-Aging & Longevity
GHK
Immune Support
PGPIPN
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.
PGPIPN is a bioactive hexapeptide (Pro-Gly-Pro-Ile-Pro-Asn) derived from beta-casein during enzymatic digestion. It exhibits anti-inflammatory properties via opioid receptor modulation and cytokine suppression, making it relevant for gut health, systemic inflammation, and as a component of casein-derived functional foods.
Half-Life
Extremely short as free peptide; tissue binding extends local effects
Estimated 30-120 minutes (peptide degradation)
Admin Route
SubQ, Topical, Oral
Oral, Subcutaneous (research)
Research
Typical Dose
100–500 mcg
200-500 mg per day
Frequency
Daily or 5x per week
Once or twice 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
  • Anti-inflammatory effects via cytokine suppression
  • Gut mucosal protection and intestinal barrier support
  • Opioid receptor modulation for gut motility regulation
  • Potential analgesic activity via central and peripheral opioid pathways
  • Explored for inflammatory bowel conditions and gut dysbiosis
  • Natural origin (food-derived) with favorable safety profile
Side Effects
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
  • Generally very well-tolerated given food-derived origin
  • Theoretical opioid-mediated constipation at high doses
  • Rare milk protein allergy in casein-sensitive individuals
Stacks With