Vitamin B12 deficiency

About Vitamin B12 deficiency

Vitamin B12 deficiency impairs the production of healthy red blood cells and the function of nerves. Symptoms range from fatigue and pallor to numbness, tingling, balance problems, memory changes, and a sore tongue. It is most common in older adults, vegans, those on long-term acid suppression or metformin, and patients with autoimmune pernicious anemia or prior gastric surgery. Diagnosis combines a serum B12, sometimes with methylmalonic acid. Treatment is oral high-dose B12 for mild cases and intramuscular cyanocobalamin or hydroxocobalamin when absorption is impaired.