GHK-Cu
Topical copper-peptide cosmetics and injectable GHK-Cu are different evidence questions. Limited topical studies do not establish systemic repair or lifespan extension. FDA flags injectable GHK-Cu for potential immunogenicity and limited human safety information.
Use cosmetic products according to their own instructions; do not extrapolate their results to injections. No validated injectable anti-ageing regimen. Skin symptoms still need dermatological assessment when persistent.
