cat b12 injection cost Vitamin B-12 Injection, 3,000 mcg/mL Cyanocobalamin (Vitamin B12) Injection is sold as an FDA approved generic drug Rx Vitamin B12 Injection 3000mcg/ml

"Greenspan's Basic & Clinical Endocrinology 10th Edition" Journal of Applied Physiology

Neelakantan H, Vance V, Wetzel MD, Wang HY, McHardy SF, Finnerty CC, Hommel JD, Watowich SJ. Selective and membrane-permeable small molecule inhibitors of nicotinamide N-methyltransferase reverse high-fat diet-induced obesity in mice. Biochem Pharmacol. 2018 Jul;154:161-171. doi: 10.1016/j.bcp.2018.05.003. Epub 2018 May 5. PMID: 29738706; PMCID: PMC6015571

During digestion, vitamin B12 is usually removed from protein and then sent straight into the bloodstream

They are marked in Units on the insulin syringe barrel (see illustration)

I am not a medically trained person but I've had Pernicious Anaemia (one of many causes of B12 deficiency) for more than 50 years