Peptide Skincare & BeautySkin science and ingredient guides

Ingredient or product comparison

GHK-Cu Cycle Protocols: Administration Comparison

4 weeks 1.5–2mg Acute wound healing, post-surgical tissue repair, initial collagen response observation Collagen gene upregulation detectable by week 2; tissue-level changes (wound closure rate, tensile strength) measurable by week 3–4 Optimal for time-sensiti

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  • 4 weeks
  • 1.5–2mg
  • Acute wound healing, post-surgical tissue repair, initial collagen response observation
  • Collagen gene upregulation detectable by week 2; tissue-level changes (wound closure rate, tensile strength) measurable by week 3–4
  • Optimal for time-sensitive healing studies where endpoints are defined within 30 days. Extend to 6 weeks only if baseline tissue damage is extensive or prior collagen synthesis is impaired.
  • 6 weeks
  • 2mg
  • Scar tissue remodelling, photoaging reversal, dermal thickness improvement
  • Dermal collagen density increase measurable by week 4; elasticity and texture improvements apparent by week 5–6
  • Standard protocol for aesthetic research applications. Provides full collagen turnover cycle without extending beyond the peptide's effective signalling window.
  • 8 weeks
  • 2–3mg
  • Chronic wound observation, deep dermal restructuring, extracellular matrix remodelling in aged tissue
  • MMP downregulation sustained through week 6; maximal collagen fibril organisation by week 7–8
  • Reserved for cases where baseline collagen synthesis is severely impaired or tissue requires extended observation. Extending beyond 8 weeks shows minimal additional benefit—GHK-Cu's signalling effect plateaus.
  • Split dosing (2× daily)
  • 1mg each
  • Previously used in early research models before half-life data clarified optimal administration
  • No advantage over once-daily 2mg; increases injection burden without improving tissue outcomes
  • Obsolete protocol—research from 2015 onward confirms once-daily dosing maintains tissue-level activity for 24 hours. Split dosing adds complexity without benefit.