In an adult with pattern hair loss or diffuse thinning and no known copper allergy, what is the recommended firstline topical peptide (copperpeptide, GHKCu) regimen? 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 Peptide: Benefits & Usage The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline