Taking B12 for energy? The evidence says you're probably wasting your money. B12 is only powerful in one situation: when you're deficient. Not tired. Not run down. Not a bit low on Did I miss anything? Pernicious Anemia is life threatening chronic autoimmune disease. And no, it's NOT just a vitamin deficiency and or anemia. B12 deficiency will affect EVERY SINGLE PART OF YOUR BODY. Side Effects of B12 Injection (Common and Serious) Credihealth 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 What Conditions Do B12 Injections Help Treat in Shoreline, WA?