ABSTRACT

Prolonged use of proton-pump inhibitors (PPI) may result in vitamin B12 deficiency as a consequence of impaired release of protein-bound dietary vitamin B12 from food in a nonacid environment. Herein, we described a case of vitaminB12 deficiency associated with three months use of PPI which was used to reduce gastric side effects of steroid in a patient with chronic graft versus host disease (cGVHD). Malabsorption of proteinbound vitamin B12 has been demonstrated with the prolonged use of PPI. Although monitoring these patients is not routinely recommended for side effects, patients with chronic disease should be followed-up more carefully.