best place to buy b12 injections vitamin injectable vials Vitamin B12 Hydroxocobalamin 1mg/1ml x 20 vials ( 4 x 5 packs ) sheep and swine as needed Vitamin B-12 Injection, 5,000 mcg/mL,
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LeWine, MD, Chief Medical Editor, Harvard Health Publishing
Department of Health and Human Services, ods.od.nih.gov/factsheets/VitaminB6-HealthProfessional/

An IV infusion typically lasts 30 to 60 minutes, depending on the volume of fluids and the specific nutrient formulation administered

This means that it is not possible to overdose on vitamin B12, and as far as we know there is no upper limit on the amount of B12 that can be taken safely by an otherwise healthy person
