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ToolsCompareGHRP-6 vs GHK-Cu

GHRP-6 vs GHK-Cu

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

Growth Hormone Peptides
GHRP-6
Skin & CosmeticRecovery & RepairAnti-Aging & Longevity
GHK-Cu
Summary
GHRP-6 is the original synthetic GH-releasing peptide and a potent ghrelin receptor agonist. It produces strong GH pulses but is notorious for a significant hunger surge 30–45 minutes post-injection. This hunger side effect makes it less preferred than Ipamorelin or GHRP-2 for most protocols but can be useful in patients with appetite deficiency.
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.
Half-Life
15–60 minutes
2–4 hours
Admin Route
SubQ, Intranasal
SubQ, Topical
Research
Typical Dose
100–300 mcg
1–3 mg
Frequency
2–3 times daily
3–5 times per week
Key Benefits
  • Strong GH stimulation
  • Elevated IGF-1
  • Muscle growth and recovery support
  • Potential anti-inflammatory effects at GI level
  • Useful for patients with appetite deficiency or cachexia
  • Enhanced recovery from training
  • 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
Side Effects
  • Intense hunger surge (30–45 min post-injection)
  • Water retention
  • Elevated cortisol (modest)
  • Elevated prolactin (modest)
  • +2 more
  • Temporary blue-green discoloration at injection site (from copper — harmless)
  • Post-injection sting (brief)
  • Skin irritation with topical use (rare)
Stacks With