GHK CU Hair Loss & Regrowth Treatment Therapy Vitality Health Copper Peptide Hair Growth Serum AHK Cu & GHK Cu + Licorice Peptide Labz GHK Cu Copper Peptide for Hair Loss: Results, Mechanism, and What to Expect Copper Peptide Hair Growth Serum AHK Cu & GHK Cu + Licorice Peptide Labz Topical or SubQ GHK Cu? Same molecule. Very different purposes. Topical you apply it on your skin. Think of it as feeding your skin from the outside. In a 12 week study of