A Case of Severe Proton Pump Inhibitor-Induced Hypomagnesemia Refractory to Continuous Oral and Intravenous Magnesium Replenishment

Proton pump inhibitors (PPIs) are frequently used medications to treat a wide variety of gastrointestinal conditions. By irreversibly inhibiting the hydrogen-potassium ATPase pump, they remarkably reduce gastric acid secretion. However, chronic PPI intake can result in serious complications, including severe hypomagnesemia. The following case report presents a severe case of refractory PPI-induced hypomagnesemia (PPIH), resistant to continuous oral and intravenous magnesium replacement, in a 70-year-old male patient, with a long history of PPI use due to persistent epigastric pain. Upon each of the 10 admissions to the hospital, he presented with severe signs and symptoms of hypomagnesemia, such as nausea, muscle fasciculation, diffuse cramps, weakness, neuromuscular irritability, and ECG disturbances, including non-specific T-wave abnormalities. In fact, PPIH has been reported for the first time in 2006. It is believed that the excessive, chronic intake of PPIs can disturb the normal functioning of the transient receptor potential melastatin 6/7 (TRPM 6/7), which is the main pathway of active intestinal magnesium absorption, leading to hypomagnesemia. PPIH is typically characterized by stubborn resistance to oral and intravenous magnesium replenishment but usually resolves after PPI withdrawal. Hence, despite being among the safest and most commonly prescribed drugs, PPI intake should be closely monitored when prolonged usage is planned. Additionally, continuous follow-up and regular assessment of serum magnesium levels are crucial to avoid the occurrence of PPIH and to prevent its potentially deleterious complications, including life-threatening arrhythmias.