Vitamin B12 deficiency affects approximately 5% of Canadian adults. Deficiencies are primarily the result of a lack of intrinsic factor (pernicious anemia). Vitamin B12 absorption can also be affected by the regular use of proton pump inhibitors. There is a large body of evidence supporting the efficacy of oral B12 administration in most cases related to pernicious anemia, malabsorption or malnutrition. The use of oral vitamin B12 is cost effective. Furthermore, using the oral formulation will decrease the need for unnecessary clinic visits for vitamin B12 injection, improve efficiency and decrease costs without compromising patient care. After the initiation of therapy, serum vitamin B12 concentrations should be monitored to assess for efficacy. Given the lack of conclusive evidence, vitamin B12 injections should still be considered for patients with severe neurological involvement, ileectomy and significant malabsorption syndromes.
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