Is this the right size needle for im injections? : r B12_Deficiency Best Needle For B12 Injections (Size & Gauge) PA Relief B12 Injection sites + How to use B12 Shots Safely 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 Q.) The appropriate needle gauge for intradermal injection is: A) 20G B) 22G C) 25G D) 26G Treating Severe Vitamin B12 Deficiency B12 IM Injection