Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu Cycle Protocols: Injection vs Topical Comparison

Subcutaneous Injection 0.5–2mg daily 85–95% systemic 8–12 weeks Deep dermal remodeling, wound healing research, systemic collagen synthesis studies Topical Serum (2–5% formulation) Applied 1–2× daily 3–8% dermal penetration 12–16 weeks Localized photoaging, su

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  • Subcutaneous Injection
  • 0.5–2mg daily
  • 85–95% systemic
  • 8–12 weeks
  • Deep dermal remodeling, wound healing research, systemic collagen synthesis studies
  • Topical Serum (2–5% formulation)
  • Applied 1–2× daily
  • 3–8% dermal penetration
  • 12–16 weeks
  • Localized photoaging, surface texture improvement, minimal systemic exposure
  • Microneedling + Topical
  • 1–2% solution post-needling
  • 15–25% enhanced penetration
  • 6–8 week cycles
  • 6–8 weeks
  • Targeted scar remodeling, localized collagen induction, combines mechanical and biochemical stimuli