metabolism of glutathione A mathematical model | Theoretical Biology and Medical Modelling GLUTATHIONE SYNTHESIS - PMC

As with any procedure that involves inserting a needle into a vein, there are also risks of discomfort, bruising, infection or reaction at the site

Prevention starts immediately with daily use

The copper content of GHK-Cu formulations has been a theoretical safety consideration, given that excessive copper can be toxic - however, the amounts used in cosmetic and research applications are extremely small, the copper is tightly chelated by the peptide (reducing free copper availability), and topical absorption of copper from these products appears minimal and well below levels that would cause systemic copper accumulation or toxicity

For instance, ossicle formation in Achilles tendon tissue appears with osteogenic protein 1 (OP-1) (Forslund and Aspenberg, 1998)