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 Cyanocobalamin (B12) Injection 1000 mcg mL, Multiple Dose Vial 1 mL, 25 Tray McGuff How often do you obtain B12 injections for weight loss? B12 Injection Frequency: How Often Should You Get a B12 Shot? Liv Hospital Are Vitamin B12 Shots Right for You? Boost Energy and Wellness with Rx B12 Injections 10 mg High Dose Vitamin B12 LifespanningRx