GHK Cu, engineered for day and night If you wish to take advantage of both formulations, we recommend applying Copper Amino Isolate Serum 3 1:1 (CAIS3) in the morning and Copper Amino Most people treat GHK Cu like it's only for hair and skin. The real leverage is in the copper signaling + repair pathways that everyone overlooks. You don't need every peptide under the GHK Cu Dosage and Protocol: A Medical Provider's Guide to the 30 Day Cycle Perfect B Does GHK Cu Regrow Hair? Here's What the Research Shows