B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Why Do I Feel Worse After My B12 Injection? Understanding Post Injecti Oxford Origins 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 Experiencing any of these symptoms? B12 supplementation might be right for you. Some causes of low B12 are diet, alcohol use, certain diseases like Chrohn's and Celiac Disease, and Gastric Bypass surgery, Why Do I Feel Worse After My B12 Injection? Causes & Management Bolt Pharmacy