ghk-cu lysyl oxidase for Hair Growth: Protocols Protective Functions of β-Alanyl-L-Histidine and
Description
A complete kit includes: A sealed vial or glass ampoule of B12 (cyanocobalamin or methylcobalamin) A 3 mL syringe A drawing needle (typically 18-21 gauge) An injecting needle: 22-25 gauge, 1 to 1.5 inch for intramuscular (IM)

Yes, GHK-Cu can be photosensitive, meaning light exposure can contribute to its degradation
As the body ramps up red blood cell production in response to B12, potassium can be used up, so your provider may recommend monitoring it with a blood test

As with many things, the individual will sort out the most effective method for them

Some patients, especially those on long-term or high-dose B12 treatment, may develop complications like: 1