Subcutaneous injection: Definition and what to expect The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline Why is the injection site painful after administering GHK Cu (Glycyl L Histidyl L Lysine Copper) 2mg mixed with normal saline? Dubai In Home GHK Cu Tripeptide Injection Book Private Therapy 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 Peptide Injection Reactions: Why Redness and Lumps Happen (And How to Fix Them)