b complex and b12 injection benefits Vitamin Injections: What You Need To Know What are the benefits of

The injection is providing you with the necessary B vitamins regardless of your food intake, which is helpful especially if you have trouble eating a balanced diet (due to illness or other reasons)

Why does needle size matter

The treatment itself was comfortable (with numbing of course) , and the results are definitely noticeable

[9] Visual disturbances have been reported in patients with Leber hereditary optic neuropathy, and rapid B12 administration may precipitate optic nerve atrophy in this genetically predisposed population, mandating extreme caution or alternative therapy

That can slow how the dose is used and is a known issue, particularly in women and larger patients where there is more tissue to pass through