Vitamin B 12 intramuscular injections are also used therapeutically to help restore energy and combat various symptoms related to such deficiencies. Vitamin B 12 is essential to the development of healthy blood cells, nerve B12 Shots at Home: How, Where & How Often to Inject Yourself AZ IV Medics Vitamin B12 Shots in Canton, MI: What You Need to Know B12 Injections for Energy: Benefits and How It Works AZ IV Medics