GHK Cu Peptide Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy Cu GHK vs Tretinoin: The Anti Aging Showdown Some people notice their skin looks worse before it improves with GHK Cu. This temporary phase is often called the copper uglies., #skincare, #ghkcu, #skinhealth, #longevity, #peptides 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,