GHK Cu is the compound your body made at 25 and quietly stopped making. Most people find it in overpriced serums. Few understand what it actually does, or what happens when you're not Peptides are often well tolerated, but they can still cause temporary reactions while the body adapts. Some commonly reported effects include: BPC 157 headaches, nausea, increased appetite TB 500 Can GHK Cu Be Taken Orally? Oral GHK Cu Bioavailability, Tablets & Copper Peptide Safety Neurogan Health GHK Cu Cooper Peptide: The Complete Skin & Repair Guide (2026)