Ingredient or product comparison
GHK-Cu Cosmetic Downstream Effects: Form Comparison
Topical serum (aqueous) Epidermis + upper dermis Negligible systemic absorption 0.5–2.0% Oxidizes rapidly; requires airtight packaging + refrigeration Best for surface-level effects (pigmentation, barrier repair). Limited deep dermal penetration without penetr
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- Topical serum (aqueous)
- Epidermis + upper dermis
- Negligible systemic absorption
- 0.5–2.0%
- Oxidizes rapidly; requires airtight packaging + refrigeration
- Best for surface-level effects (pigmentation, barrier repair). Limited deep dermal penetration without penetration enhancers.
- Topical cream (lipid-based)
- Upper dermis (with penetration enhancers)
- 1.0–3.0%
- More stable than aqueous; copper can still oxidize over 6–12 months
- Improved penetration vs aqueous; better for wrinkle reduction. Requires occlusive base (ceramides, cholesterol) to prevent evaporative loss.
- Subcutaneous injection
- Full dermal depth + systemic distribution
- Measurable (peak ~2–4 hours post-injection)
- 5–50mg per session
- Highly unstable; reconstituted solution degrades within 24–48 hours
- Delivers GHK-Cu directly to target tissue. Used in clinical wound healing studies. Not FDA-approved for cosmetic use.
- Microneedling + topical
- Deep dermis (microchannel-mediated)
- Minimal systemic absorption
- 2.0–5.0% applied post-needling
- Same as topical; must be applied immediately after needling before channels close
- Combines mechanical collagen induction with peptide signaling. Clinical data shows additive effects vs microneedling alone. Requires sterile technique.
- Oral supplement (capsule)
- Systemic. Distributed via bloodstream
- Variable (depends on GI absorption)
- 50–200mg daily
- Degraded by gastric acid and peptidases; bioavailability ~5–15%
- Weakest evidence base. Peptides are broken into amino acids before absorption. No controlled trials demonstrate efficacy for skin outcomes.