GHK CU Beverly Hills Rejuvenation Center Redness after a peptide injection can feel alarming but in most cases, it's completely normal. If you've noticed a pink or red halo at the injection site especially with peptides like Squalane + Copper Peptide (GHK Cu) Rapid Plumping Serum GHK CU: 100mg Supernova Peptides Intermediate Cu(II) Thiolate Species in the Reduction of Cu(II)GHK by Glutathione: A Handy Chelate for Biological Cu(II) Reduction Inorganic Chemistry