Advanced GHK Cu Face Cream 2400mg 4% Firmer Skin Neurogan Neurogan Health GHK Cu Peptide Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy Should Bodybuilders Take GHK Cu? Neurogan Health GHK Cu, the copper peptide, is a game changing injectable for radiant skin and so much more, , , Heres what it can do:, Boost collagen for smoother, firmer skin, Anti aging improves fine 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK