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 Ghk Cu Peptide Injection IV Vitamin Therapy week 3 of using GHK Cu peptide pin. If I take a photo with the same lighting? How much of a difference do you think there will be? #ghkcu #peptide #look #looksmaxing #glowup 7 days on GHK Cu. Here's my honest update. I'm not going to hype this up because the real results don't even start until week 46. But something is already happening.