Struggling with B12 injection frequency? Here's what you need to know If you have Pernicious Anaemia (PA) or B12 deficiency due to autoimmune gastritis, NHS guidance is clear: You should The B12 Shot: What Every Human Needs to Know About Injectable Vitamin B12 Vitamin B12 Deficiency: Vitamin B12 deficiency is a nutritional or absorption related disorder leading to impaired DNA synthesis and neurologic dysfunction, commonly presenting with megaloblastic anemia and neuropsychiatric symptoms. Physiological Vitamin Injections in North Georgia Mike's Vitamin Infusions 3 monthly injections : r B12_Deficiency