Most kidney stones are Calcium Oxalate.
Theralogix makes an over the counter supplement, Theralith, that has Potassium (K+), Magnesium (Mg++) and Vit B6.
There is an inverse relationship in the kidney, excretion of Sodium (Na+) vs. K+, Calcium (Ca++) vs. Mg++. In essence if you're excreting K+ you can't excrete as much Na+, it's either or. Same with Mg++ and Ca++.
So by taking a product with Mg++ and K+, you excrete less Ca++ and Na+, thus have less stone making components to make stones.
Google it.
DF