GHK Cu Copper Peptide for Hair Loss: Results, Mechanism, and What to Expect Before and after begins with consistency. Our 10% GHK Cu formula is engineered for deep absorption to support scalp health and visible density. Copper Peptide Hair Growth Serum for Hair Loss & Thinning Hair Feline Skinscience GHK Cu is one of the most talked about peptides in aesthetics right now. But how much of what you have heard about it is actually true?, Copper peptide, known as GHK Cu, has a growing body of peer Okay but Ive only been using GHK Cu for 2 weeks and Im already noticing my skin looking firmer and my fine lines softening. I wasnt expecting to see results this fast but Im loving the glow. DM