The GHK Cu pen works. But needles at home were never the answer. We took the same clinically backed copper peptide complex and put it into a serum you can use in 30 seconds, Frontiers Copper toxicity and deficiency: the vicious cycle at the core of protein aggregation in ALS The Effect of the Human Peptide GHK on Gene Expression Relevant to Nervous System Function and Cognitive Decline Copper Peptide (GHK Cu): Clinical Uses, Stability & Compounding Tips