GHK Cu Peptide Progress: Week 3 Results 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 If your GHK Cu or MOTS C injection leaves welts and burns like a hornet, it's usually not the peptide it's the technique. A few small tweaks can turn a sting into almost GHK Cu for Skin: SIGNAL's Guide to Rejuvenation