Functional hypoparathyroidism secondary to magnesium deficiency in long-term users of proton pump inhibitor

Gastroesophageal reflux disease (GERD) is a gastrointestinal motility disorder that results from the reflux of stomach contents into the esophagus resulting in symptoms or complications. GERD is now widely prevalent around the world, with clear evidence of increasing prevalence in many developing countries. Treatment for most people with GERD includes lifestyle changes and medication. Proton pump inhibitors (PPIs) are a mainstay therapy for all gastric acid-related diseases. Long-term use of PPIs is associated with hypomagnesaemia, hypokalemia, hypocalcaemia, osteoporosis and bone fractures, chronic renal disease, acute renal disease, and other. Clinical concerns arise from a small but growing number of case reports presenting PPI-induced hypomagnesaemia. In 2011 the U.S. Food and Drug Administration is informing the public that prescription PPI may cause low serum magnesium levels if taken for prolonged periods of time. In this article, we present the case of a 56-year-old patient with muscle cramps, violation of cardiac rhythm, lethargy and other caused by hypomagnesaemia, hypocalcaemia and hypokalemia with a low parathyroid hormone level while using a PPI. After magnesium repletion abnormalities resolved. A causal relation with PPI use was supported by the recurrence of hypomagnesaemia after re-challenge.