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ToolsCompareGHK-Cu vs Retatrutide

GHK-Cu vs Retatrutide

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

Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu
GLP-1 / Weight Loss Agonists
Retatrutide
Summary
GHK-Cu is a naturally occurring copper complex that declines with age. It is one of the most studied anti-aging peptides, known for powerful skin rejuvenation, wound healing, and tissue remodeling effects.
Retatrutide is an investigational triple receptor agonist targeting GLP-1, GIP, and glucagon receptors simultaneously. Phase 2 trials showed an unprecedented average 24% body weight reduction at 48 weeks — exceeding any approved medication to date. It is in Phase 3 trials as of 2024.
Half-Life
2–4 hours
~10–12 days
Admin Route
SubQ, Topical
SubQ
Research
Typical Dose
1–3 mg
0.5 mg → 1 mg → 2 mg → 4 mg → 8 mg → 12 mg
Frequency
3–5 times per week
Once weekly
Key Benefits
  • Reduces wrinkles and fine lines
  • Improves skin firmness and elasticity
  • Accelerates wound healing
  • Reduces inflammation and oxidative damage
  • Promotes hair growth and thickness
  • Supports collagen and elastin production
  • May improve overall skin health and appearance
  • Resets aged fibroblast behavior
  • Anti-fibrotic — reduces scar tissue formation
  • ~24% body weight reduction at 48 weeks in Phase 2 (highest dose)
  • Superior to both semaglutide and tirzepatide in early trial comparisons
  • Triple receptor mechanism addresses multiple obesity pathways
  • Significant reduction in liver fat (MASH/NAFLD indication being studied)
  • Improved cardiovascular and metabolic markers
  • Once-weekly dosing
  • Potential for greatest weight loss of any currently investigated compound
Side Effects
  • Temporary blue-green discoloration at injection site (from copper — harmless)
  • Post-injection sting (brief)
  • Skin irritation with topical use (rare)
  • Nausea and vomiting (common during titration, similar to semaglutide/tirzepatide)
  • Diarrhea
  • Constipation
  • Heart rate increase (from glucagon receptor agonism)
  • +2 more
Stacks With