Prevention of nephrolithiasis.

The high incidence of recurrence after an initial stone event underscores the need for an effective medical prophylactic program. Dietary modification and drug therapies have long been advocated to reduce the likelihood of stone recurrence. While the efficacy of a high fluid intake has been validated in a randomized trial, the benefit of other dietary measures is based on modulation of urinary stone risk factors and outcomes derived from observational studies. Several drug therapies have been evaluated in a limited number of prospective, randomized trials and efficacy has been demonstrated for thiazides, allopurinol and alkali citrate in some populations of recurrent stone formers. The role of selective versus nonselective therapy for stone prevention awaits further study.