GHK Cu Topical vs Injection Which is the Better Copper Peptide Form? Most people think GHK Cu works because it's a skin peptide. That's surface level thinking. #GHK Cu doesn't start with wrinkles, scars, or hairlines. It starts with cellular repair signalling. GHK Cu is a copper peptide GHK CU : r Peptidesource GHK CU Apollo Peptide Sciences GHK Cu Copper Peptide Supplement, Promotes Skin Repair, Reduces Wrinkles CTDE PARIVAR