Severe symptomatic hypomagnesaemia induced by the chronic use of proton pump inhibitors: a case report of a patient with Zollinger-Ellison syndrome.

The association between proton pump inhibitor (PPI) therapy and hypomagnesaemia has been recognized since 2006. We report the case of a 51-year-old woman who developed severe symptomatic hypomagnesaemia after a long-term PPI therapy given for recurrent peptic ulcer disease. Hypomagnesaemia could only partially be resolved during substitution therapy, but was corrected after withdrawal of the PPI. Recurrence of hypomagnesaemia occurred after retreatment with PPIs, supporting the causal relationship. An underlying gastric acid hypersecretion (Zollinger-Ellison syndrome) was highly suspected and eventually controlled by a combination of a histamine 2-receptor antagonist and octreotide, without the need for further PPI therapy after 2 years of follow-up.