Hypocalcemia secondary to hypomagnesemia in a patient on liraglutide

A 73-year-old man with type 2 diabetes on Liraglutide with a history of coronary artery disease. Admitted to emergency for abdominal pain, severe diarrhea and episodes of tetany attacks. Laboratory workup reveals hypomagnesemia, hypocalcemia and normal parathormone (PTH). After intravenous administration of magnesium and calcium, the blood ionogram quickly normalized. In addition, plasma levels of intact parathyroid hormone increased immediately after magnesium administration. Strongly suggests that hypocalcemia resulted from a disruption of adequate parathyroid hormone secretion caused by hypomagnesemia which in turn was caused by severe diarrhea under treatment with Liraglutide. •Serum magnesium concentration is determined by the interaction of intestinal absorption and renal excretion.•Hypomagnesemia may occur following an insufficient intake of magnesium, an increase in renal or gastrointestinal losses.•Severe diarrhea from drug like Liraglutide may lead to significant drop in magnesium and calcium levels.•Several drugs are known to cause hypomagnesemia, including proton pump inhibitors (PPI).