Effect of Cystone® on urinary composition and stone formation over a one year period.

The short version

This small randomized trial with 10 people explored whether Cystone, an Ayurvedic herbal tablet sold for kidney stones, changes the urine chemistry that drives stone formation or reduces the amount of stone in the kidneys. Kidney stones are painful and often recur, and the available prevention options (diet changes and medicines such as thiazides, potassium citrate and allopurinol) have drawbacks. Cystone is a blend of seven plants plus purified Shilajeet and a mineral preparation (bhasma), traditionally used for urinary problems, but the authors say earlier studies of it were small and poorly controlled. Ten adults from the Mayo Stone Clinic who repeatedly formed calcium oxalate stones took two Cystone tablets twice a day, or matching placebo, for six weeks each in a crossover design, switching after a one-week break. All then took Cystone openly for another 48 weeks. Urine collected over 24 hours measured how saturated it was with stone-forming minerals. CT scans at the start and after a year, scored with the same method used for heart-artery calcium, measured stone volume, and a radiologist reviewed them without knowing the timing. Cystone did not change urinary measurements in the short term (6 weeks) or the long term (52 weeks). Average stone burden per kidney actually rose from 93 to 114 cubic millimetres (P = 0.07) and from 108 to 136 on the Agatston scale (P = 0.10), neither statistically significant. The radiologist counted 8 kidneys with more stone, 8 unchanged and 2 with less, and four kidneys passed stones spontaneously. No participant described side effects they attributed to Cystone. The authors conclude the trial does not support Cystone for preventing calcium oxalate stones, while noting the sample was tiny, participants had stones that standard treatment had not controlled, and some factors that inhibit stone formation were not measured. They say a longer study with more patients would be needed to look at stone passage or other stone types.

Key findings

• Ten adults who repeatedly form kidney stones took an Ayurvedic herbal tablet called Cystone, or a placebo, in a six-week crossover test and then took Cystone openly for a year.
• Cystone did not change the urine measurements that predict stone formation, either after 6 weeks or after 52 weeks.
• On CT scans, the average stone amount per kidney went up slightly (93 to 114 cubic millimetres), though this rise was not statistically significant.
• No participant reported side effects they attributed to the tablet.
• With only ten participants, mostly people whose stones standard treatment had not controlled, the authors say a longer, larger study would be needed to draw firmer conclusions.

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