Vitamin B12 Injection Dose: 7 Key Guidelines for Safe and Effective Treatment Liv Hospital B12 Injections for Energy: Benefits and How It Works AZ IV Medics B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Vitamin B12 (cobalamin) and folate (vitamin B9) are vitamins that serve important functions in the human body. Folate is needed for development and growth of cells (including red blood cells) and synthesis