The following are our recommended vitamin B12 injection needle size and gauge: B12 Shots Needle Size (Length) For subcutaneous B12 injections, we suggest using shorter 4-5mm needles
Rapid Relief from Symptoms Injections fix deficiency symptoms very quickly
The most studied is GHK-Cu, which stands for Glycyl-L-Histidyl-L-Lysine-Copper
BMC Microbiol
[17] Miscellaneous agents Apart from these, large doses of vitamin C, hyaluronic acid, epidermal growth factor and combinations of multiple natural extracts (natural collagen extracts, bearberry extract, Glycyrrhiza glabra extract, Lycopene, Kelp, olive leaf extract, hawthorn, jujube, sea buckthorn, starch, coix seed, pearl extracts, etc.,) are also promoted for skin whitening in the form of food or dietary supplements with no scientific evidence
For maximum benefit : Many practitioners recommend combining subcutaneous injection (for systemic effects) with topical application (for skin-specific benefits)