A Dermatologist's Take on the Copper Peptide (GHK Cu) Trend 12 weeks in, and my skin has NEVER looked better! GHK peptides are doing their thing. Alright, I need to give you an updateit's been 12 weeks since I started using GHK PSA] Finally, a Dr. explains the mechanism behind the "copper uglies" : r SkincareAddiction Ghk Cu Before And After 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 Glow Peptide Stack for Skin Rejuvenation Jennifer R. Berman MD