Effects of improved glycaemic control on calcium and magnesium homeostasis in type II diabetes.

Poorly controlled type II diabetic patients with hypomagnesaemia, hypermagnesuria, and hypercalciuria were allocated to treatment with either metformin or glipizide, to determine the effects on some indices of mineral metabolism. Despite comparable improvement in glycaemic control, assessed by glucose and haemoglobin A1, there were significant differences between the two groups in the handling of magnesium. Patients receiving metformin showed a reduction in magnesium excretion but remained hypomagnesaemic and hypercalciuric. In contrast, patients receiving glipizide exhibited little change in either magnesium or calcium excretion but showed a significant rise in serum magnesium.