how to give b12 injections to dog Vitamin B-12 Injectable for Horses, Dogs and Cats — Jeffers How to :Administer an injection
Description
This is a commonly referenced study from 1963 claiming a half-life of 5-6 days: nature.com/articles/198200a0 Although I would not cite it as an authority, the six-day half-life has also made it onto the B12 page in Wikipedia, seemingly unchallenged

Procedure J3420 may require prior authorization depending on the patients insurance plan

Greibe, E

however, kit contents may vary
Never transition their diets when they are sick because they will associate the new food with not feeling well
