Copper Peptide Hair Growth Treatment GHK cu, AHK cu, Licorice Root Extract, Ginseng Root Extact Copper Peptide Hair Growth Serum for Hair Loss & Thinning Hair Feline Skinscience If your hair has been thinning, shedding, or just not growing like it used to meet GHK Cu (copper peptide) , This tiny peptide is one of the most underrated hair regrowth ingredients out there Before and after begins with consistency. Our 10% GHK Cu formula is engineered for deep absorption to support scalp health and visible density.