Before vs. after 3 months of GHK Cu peptide therapy smoother texture, more even tone, and skin that looks healthier overall. Small peptide, big difference GHK Cu Copper Peptide: Dosage, Before and After Results, and How It Works Perfect B Neurogan Health, Copper Peptide GHK CU, 120 mcg, 60 Tablets iHerb The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline