B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Normal B12 Levels (by Age) vs. the Optimal Range PA Relief B12 INJECTIONS AND WELLNESS MATTER Loomis Best Ways to Get Vitamin B12 Shots for Thyroid Patients Our bodies need vitamin B12 to maintain healthy red blood cells, nerves, and brain function. If a person has vitamin B12 deficiency (their body does not have enough vitamin B12), they can Vitamin B12 & Hypothyroidism: What You Must Know