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: GHK Cu 50mg NewBioRx Peptide GHK CU Cream Concierge MD 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, GHK Cu Copper Peptide Neck & Face Serum