Are B12 Shots Safe? Royal Palm Beach Medical Group If I took vitamin B12 injections and folic acid along with magnesium, a B complex, and carnitine, but there was no improvement and my condition actually worsened with increased anxiety, does this mean B12 deficiency can damage your nervous system with a completely normal blood count. In a landmark NEJM study, 28% of patients with neuropsychiatric B12 damage had no anemia or macrocytosis. B12 runs Why Do I Feel Worse After My B12 Injection? Understanding Post Injecti Oxford Origins Why Do I Feel Worse After My B12 Injection: 6 Body Reactions Vitamin B12 Deficiency: Signs & Symptoms Vitamin B12 is essential for nerve health, red blood cell formation, and brain function. When B12 levels are low, symptoms often develop slowly and silently,