RESUMEN
Two alcoholic patients, a woman aged 64 and a man aged 69 years, were admitted with tetany. Both had severe electrolyte disorders, with low plasma levels of calcium, magnesium and potassium. Following mineral supplementation both patients recovered. Hypomagnesaemia plays a central role in the pathophysiology of this syndrome. Chronic alcohol abuse results in hypomagnesaemia in 30% of patients by decreasing renal tubular reabsorption. Hypomagnesaemia leads to suppression of parathyroid-hormone secretion, parathyroid-hormone resistance and vitamin-D suppression, resulting in hypocalcaemia. Hypomagnesaemia also causes kaliuresis leading to hypokalaemia. Supplementation with magnesium is crucial in the treatment of this combined electrolyte disorder.