According to the NIH Office of Dietary Supplements, vitamin B12 is available as cyanocobalamin and hydroxocobalamin, which are typically administered parenterally by intramuscular injection to bypass gastrointestinal absorption barriers
Common requirements include documented BMI meeting the threshold, proof of previous weight loss attempts (usually 3-6 months of supervised diet and exercise), at least one qualifying comorbidity, and sometimes evidence that other treatments have been tried and failed
For planned procedures, your doctor(s) will need the drug list to advise you what to stop and what not to stop
You also need to factor in things like the price, how your body reacts to the medication, if youre good with a standard dose or if you might be better served by a custom dosing schedule, and even especially in the case of brand-name drugs, whether it will be available at all when you need it
doi: 10.1016/S0140-6736(20)30925-9 2 CoronadoFMelvinSCBellRAZhaoG
J Mol Diagn 2005