Absence of evidence isnt evidence of absence its a popular argument, but its not how we should be guiding treatment decisions. In this short, I respond to a comment about GHK Cu injections for Amazon.com: Skin Perfection Copper Peptide Serum GHK CU 1% for Face & Hair Copper Peptides for Skin, Hair, & Scalp 1% Blue Liquid for Face, Neck, Body, Scalp Multi Use Serum Booster with GHK Cu Injection AgelessRx GHK Cu Revival Clinic