GHK Cu (Copper) For Sale (50mg) Core Peptides If you're using GHK Cu and it stings a little (which is common) this one's for you In this reel I'm sharing the small tweaks that have helped me make peptide injections 7 days on GHK Cu. Here's my honest update. I'm not going to hype this up because the real results don't even start until week 46. But something is already happening. 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