Ingredient or product comparison
GHK-Cu Protocol Comparison: Topical vs Subcutaneous Delivery
Different delivery methods produce different tissue-level outcomes. Here's how topical and subcutaneous protocols compare across key variables. Topical (direct application) 1–2mg in 0.1–0.2mL solution Epidermis + upper dermis (0.1–0.3mm without enhancement) 4–
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- Different delivery methods produce different tissue-level outcomes. Here's how topical and subcutaneous protocols compare across key variables.
- Topical (direct application)
- 1–2mg in 0.1–0.2mL solution
- Epidermis + upper dermis (0.1–0.3mm without enhancement)
- 4–6 weeks with daily use
- Passive diffusion through stratum corneum; limited by molecular size and charge
- Requires intact barrier; absorption drops 60–80% on damaged or inflamed skin
- Best for surface-level improvements (texture, pigmentation); combine with microneedling for deeper penetration
- Topical + microneedling (0.5–1.0mm depth)
- 1–2mg applied immediately post-needling
- Mid-dermis (0.5–1.5mm)
- 3–4 weeks with weekly needling + daily application
- Microchannels bypass stratum corneum; peptide reaches fibroblast-dense dermis
- Requires sterile technique; inflammation from needling can degrade peptide if applied too soon
- Most cost-effective method for dermal remodelling; visible collagen density increase within 8 weeks
- Subcutaneous injection
- 1–2mg per 0.1–0.2mL injection
- Deep dermis + subcutaneous fat (2–4mm)
- 2–3 weeks for localised volume; 6–8 weeks for collagen synthesis
- Direct delivery to fibroblast layer; bypasses all absorption barriers
- Requires injection skill; risk of bruising, fibrosis with repeated injections in same site
- Fastest onset for targeted areas (under-eye, nasolabial folds); rotate sites to prevent scar tissue
- Oral (experimental. Not recommended)
- 5–10mg capsule
- Systemic (degrades in gastric acid; bioavailability <5%)
- Unreliable; most studies show no measurable tissue uptake
- Intestinal absorption; peptide bond cleavage by proteases
- Copper absorption competes with zinc and iron; GI irritation common at effective doses
- No clinical evidence supports oral GHK-Cu for dermal anti-aging; topical or injectable routes required