The Bottom Line: Studies of PPI use and vitamin B12 deficiency have yielded mixed results. Absorption decreased from 3.2 to 0.9% (P ¼ 0.031) in patients on omeprazole 20 mg daily, and from 3.4 to 0.4% in patients on higher doses. Chronic PPI therapy was associated with a 46% decline in median serum B12 levels and subnormal levels in 10% of patients. Others have reported no decreased absorption of vitamin B12 . Older patients are at greatest risk and more likely to have borderline baseline levels.
References: Abraham, N. (2012). Proton pump inhibitors: Potential adverse effects. Current Opinion in Gastroenterology, 28(6), 615-620.
Summary: High-dose, chronic PPI use is prevalent, despite a high degree of comorbidity in the target population and significant treatment failures . Clinicians must remain cognizant of potential threats and ensure vigilance in their prescribing habits. PPI prescription must be tailored, using an individualized approach that limits use to robust indications