B12 Injection Frequency: How Often Should You Get a B12 Shot? Liv Hospital When a T shot is missed, most of my Patients simply begin a new start date or wait until their usual shot day to return to schedule. The reason? Youre not going to lose the effects of T overnight What Color is Vitamin B12 Injection? Dr. Scott Denny Will my B12 Injection Work Right Away? About Face Anti Aging Vitamin B12 deficiency, sometimes called cobalamin deficiency, happens when your body is either not getting enough or not absorbing enough vitamin B12 from the foods you eat. Vitamin B12 is an important B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics