GHK Cu Peptide Progress: Week 3 Results GHK Cu: My secret weapon for skin, hair, and healing, I use it two ways topical cream for my face, and subQ injections 3x a week., It boosts collagen, tightens skin, helps hair grow, and even Loose skin isnt about age alone., Its about collagen signaling., GHK Cu (copper peptide) is known for supporting pathways involved in:, Collagen and elastin production, Skin remodeling and GHK Cu: The Peptide Everyone Is Injecting (Big Mistake?)