Peptide Therapy for Pain Management and Healing Core Medical & Wellness Copper, Collagen, and Controversy: Inside the GHK Cu Buzz Copper Peptides (GHK Cu): Benefits and Side Effects Copper peptides explained what are the differences between copper peptides and GHK CU peptides? What they actually do for the skin in terms of repair and collagen, and what you can and cant mix GHK Cu might be trending, but it's not new. Before you inject yourself with this viral peptide, consider this. This copper peptide has been studied for years in skin repair and collagen signalling,