GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B Copper Peptide (GHK Cu) 2% Recovery Serum 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: The GHK Cu pen works. But needles at home were never the answer. We took the same clinically backed copper peptide complex and put it into a serum you can use in 30 seconds,