Biochemical and clinical effects of the prophylactic treatment of renal calcium stones with magnesium hydroxide.

Prophylactic treatment with magnesium hydroxide ws instituted in 56 consecutive cases with renal calcium stones. The patients had been investigated previously with regard to the magnesium metabolism. The urinary magnesium excretion increased promptly and remained on a higher level during treatment. No changes were observed in the serum or urinary calcium concentrations. Most patients have undergone treatment for at least 2 years and 45 have been free of recurrences of formations of new stones. The mean stone episode rate during treatment was 0.03 stones per year compared to 0.8 stones per year before treatment was instituted. The natural history of stone disease also was followed in 34 patients with stones who had received no prophylactic therapy and 15 have experienced recurrences after 2 years. Therefore, in comparison, treatment with magnesium hydroxide appeared to reduce the recurrence rate. Apart from minor gastrointestinal discomfort no adverse effects were observed during treatment.