Kidney stones are a global affliction causing a great deal of morbidity and economic loss.1 The prevalence of nephrolithiasis increases as societies become industrialized.2,3,4 Therefore, the worldwide burden is likely to increase in future years. A method to prevent kidney stones would be an obvious benefit. Existing treatments with evidence that supports their long term efficacy to prevent calcium oxalate kidney stones include dietary and lifestyle changes, as well as chronic use of one of three medications (thiazides, potassium citrate, and allopurinol). No new treatments have been established in decades, and these that are available have inherent problems related to patient compliance, cost, effectiveness and side effects. Therefore, a preventive treatment that would be easy to take, low in cost, safe and effective would be highly desirable.Cystone® tablets are an Ayurvedic treatment for stones, traditionally practiced in India. Many studies and long experience attest to the safety of this compound. It is also claimed that Cystone® decreases urinary supersaturation or micropulverizes and expels kidney stones.