Injection Site Redness ChemoExperts What causes skin darkening around Copper GHK (Glycyl L Histidyl L Lysine Copper) injection sites? Experiencing itching & burning from your GHK CU peptide injections? Try these to hacks:, 1. Use a longer syringe to penetrate deeper into the fat cells. , 2. Dilute the copper. Here I show you how to GHK Cu Peptide Therapy: The Definitive Clinical Guide to Gene Modulation, Protocols, and Efficacy If your GHK injection site gets irritated try this , 1. Dilute it by adding more water to the syringe , 2. Let it sit until it reaches room temperature , Also, make sure youre rotating injection