how much b12 can you inject daily Are getting enough B12? Best Vitamin B12 Injection Site:

Skin preparation Proper skin preparation reduces both infection risk and reaction risk

Who Should Choose a B12 IV Infusion Over a Shot

Supplementation with trimethylglycine (betaine) at 12g daily or SAMe (S-adenosylmethionine) at 400800mg daily can offset potential methyl donor depletion

With most drugs in psychiatry, though, short half-lives do not necessarily translate into earlier benefits, and where higher levels need to be attained sooner than can be attained by waiting for 5 half-lives, this is achieved by administering higher initial (loading) doses, or by crowding earlier doses and then spacing them out into the recommended dosing intervals