Everything You Need to Know About the FDA Peptide Ban People are turning themselves into lab rats': the injectable peptides craze sweeping the US Well actually The Guardian GHK Cu: The Copper Peptide And The Claims Around It GHK Cu is a naturally occurring copper binding tripeptide found in human plasma. Mechanistically, it's linked to tissue repair signaling, immune modulation, glycosaminoglycan and collagen A Dermatologist's Take on the Copper Peptide (GHK Cu) Trend