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ToolsCompareGHK vs AOD-9604

GHK vs AOD-9604

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

Skin & CosmeticAnti-Aging & Longevity
GHK
Fat Loss & Metabolic
AOD-9604
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.
AOD-9604 is a modified fragment of human growth hormone (residues 177-191) with an additional tyrosine residue that significantly enhances bioavailability. Originally developed as an anti-obesity drug by Metabolic Pharmaceuticals, it stimulates lipolysis and inhibits lipogenesis without the diabetogenic effects of full GH.
Half-Life
Extremely short as free peptide; tissue binding extends local effects
30-45 minutes injectable; longer with nasal spray formulation
Admin Route
SubQ, Topical, Oral
SubQ, Intranasal, Oral
Research
Typical Dose
100–500 mcg
300-600 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
  • Selective fat loss without anabolic side effects
  • No effect on blood glucose or insulin resistance
  • Improved bioavailability over Fragment 176-191
  • GRAS (Generally Recognized As Safe) status in Australia
  • Potential cartilage repair and anti-inflammatory properties
  • Does not suppress natural GH production
Side Effects
  • Excellent safety profile (naturally occurring peptide)
  • Rare: mild injection site reaction (SC)
  • No significant adverse effects identified in research
  • Localized injection site reactions
  • Headache (rare)
  • Hypoglycemia risk in combination with insulin (very rare)
Stacks With