How to draw up B12 (labeled as Methylcobalamin) Injections Transformations Weight Loss Dr. prescribed B12 injections. Pharmacy only gave me vials. Where do you get your needles and syringes? What size?? Where do I inject? : r B12_Deficiency Needle Size for B12 Injection: 5 Must Know Tips How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust Not all shots are the same here's a guide Injections are a fast, effective way to deliver medications, nutrients, and vaccines directly into the bodybut not all injections are the Insulin Syringes 31 gauge x 5 16", 0.5 mL by SureComfort