A 60-year-old woman presents with increasing fatigue, shortness of breath, and pale skin. She has been taking an over-the-counter proton pump inhibitor for heartburn for the past year. Lab tests show low hemoglobin and mean corpuscular volume. What might be the diagnosis?
The patient's symptoms and lab results suggest iron deficiency anemia, which could be due to malabsorption of dietary iron. Chronic use of proton pump inhibitors can decrease stomach acid and impair absorption of iron. The patient should be evaluated for other causes of iron deficiency, but consideration should also be given to stopping the PPI or replacing it with a less potent antacid, in addition to starting iron supplementation.