Uses and Benefits #ghk GHK Cu is a naturally occurring peptide in human plasma that declines with age. When used in injections (usually subcutaneous), it can offer various benefits: Skin Rejuvenation and Anti Aging: 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 Shampoo to Use After Hair Transplant STEMBOTANY 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