Thiazides in the prophylactic treatment of recurrent idiopathic kidney stones.

In a double-blind prospective clinical study patients with at least two verified episodes of urolithiasis, but stone-free at the time of inclusion in the study, were subjected to prophylactic treatment with either bendroflumethiazide (2.5 mg) + 573 mg potassium chloride 3 times a day, or placebo. The material included a total of 22 patients, all males, aged 20-49 years. We found a clear tendency to reduced stone formation in the group treated with the active drug (P less than 0.01). Calcium excretion was reduced by 25-50% in 7 of 12 patients treated with thiazide.