Table 6.7-1. Causes of abnormal serum magnesium levels

Low serum magnesium

Decreased intake or absorption

– Decreased intake

– Malabsorption (short bowel syndrome, steatorrhea, diarrhea, vomiting)


– Diuretics (especially thiazides)

– Proton pump inhibitors

– Foscarnet, amphotericin B, aminoglycosides, pentamidine, rapamycin

– Anticancer drugs (cisplatin, carboplatin)

– Immunosuppressants (calcineurin inhibitors: tacrolimus, cyclosporine A)

– EGRF inhibitors (cetuximab)

Rare genetic disorders

– Familial hypomagnesemia with secondary hypocalcemia (TRPM6 gene mutation)

– Autosomal dominant hypocalcemia (activating mutation in the CASR gene)

– Familial hypomagnesemia with hypercalciuria and nephrocalcinosis

High serum magnesium

– Magnesium administration for eclampsia or preeclampsia

– Intake in laxatives or cathartics

– Metabolic syndromes (familial hypocalciuric hypercalcemia)

– Chronic kidney disease

EGFR, epidermal growth factor receptor.