HOW TO SELF INJECT B12 AT HOME with Dr. Tyler Rogers If you've been prescribed vitamin B12 shots or exploring at home wellness, this step by step guide will walk you through how 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 Sizes Explained: Choosing the Right Gauge for Different Injections Needles How to self inject intramuscular vitamin B12 Overview Guy's and St Thomas' NHS Foundation Trust