GHK Cu Dosage and Protocol: A Medical Provider's Guide to the 30 Day Cycle Perfect B Understanding the Difference Between Glow and GHKCU Peptides Before vs. after 3 months of GHK Cu peptide therapy smoother texture, more even tone, and skin that looks healthier overall. Small peptide, big difference What is GHK Cu and Why is Everyone Talking About It? GHK Cu (Copper Peptide) is a powerful, naturally occurring compound in the body that plays a key role in skin health