Treatment of idiopathic renal magnesium wasting with amiloride.

We report a case of an 18-year-old female who presented with severe hypomagnesmia due to idiopathic renal magnesium wasting. Only a partial response was noted with magnesium oxide replacement. Treatment with the potassium-sparing diuretic amiloride led to a further rise in the serum magnesium level, a decrease in the fractional excretion of magnesium and improvement in her symptoms. This case demonstrates an effective treatment for idiopathic renal magnesium wasting.