[Clinical significance of serum magnesium concentration in thyrotoxicosis (author's transl)].

Thyrotoxicosis is associated with hypomagnesemia. Therapy leads to restoration of serum magnesium concentration. The clinical significance of the disturbance in magnesium metabolism is discussed on results of two groups of patients with hyperthyroidism. One group of 7 patients with high serum thyroxine levels and mild clinical signs of thyrotoxicosis showed a normal magnesium concentration in serum. In a second group with further 7 patients serum magnesium level did not increase during therapy while thyroxine decreased in spite of lack of clinical improvement. The results suggest that serum magnesium concentration is primarily determined by 1-triiodothyronine.