GHK CU Peptide for Skin Rejuvenation Wittmer Rejuvenation Clinic GHK Cu 50mg Particle Peptides Glow from within Introducing the Glow Stack a personalised peptide protocol designed to support collagen production, skin renewal, and a radiant complexion. Because healthy skin is more than skincare it's 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