GHK-Cu dosing splits cleanly by route, and the evidence is very uneven between the two. The human data is almost entirely topical: cosmetic serums and creams use roughly 1 – 3% GHK-Cu once daily, and that is where the placebo-controlled facial studies sit. Injectable dosing is a different story.[1][2]
Reviewed for accuracy · Last reviewed July 7, 2026Injectable GHK-Cu figures, commonly cited around 1 – 2 mg once daily over a 4 – 8 week cycle, are community-driven and are not backed by published human dosing studies. Treat them as anecdotal. One practical note: reconstituted GHK-Cu turns deep blue from the bound copper ion, which is normal and not a sign the peptide has degraded.
This page is an independent educational reference and is not medical advice. Talk to a doctor before starting any compound.