Practice Nurse Professional Resources for General Practice Nursing Subcutaneous injecting WithYou B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics CYANOCOBALAMIN INJECTION, USP 30000 mcg 30 mL (1000 mcg mL) 30 mL VIAL Not all shots are the same here's a guide Injections are a fast, effective way to deliver medications, nutrients, and vaccines directly into the body but not all injections are the same.