GHK Cu Copper Peptide Regeneration, Skin Renewal & Anti Age Just started GHK Cu? Here's what to expect This isn't an overnight peptide, it builds Weeks 12: You may start noticing small shiftsskin feels a bit smoother, nails a little stronger Weeks 34: 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK GHK Cu Copper Peptide Serum Private Label Skin Repair A Dermatologist's Take on the Copper Peptide (GHK Cu) Trend