The juice from lemons is supposedly capable of dissolving calcium-based kidney stones.
If anyone decides to try this and wants to make more than just a glass-full at one time, you can use a gallon size container. Pour one cup of lemon juice into the container and finish filling with water. You can use reconstituted lemon juice or fresh lemon juice from lemons. If concentrated lemon juice is used you’d naturally use less than a cup; check the label for measurements. You may want to use a straw each time you drink this as its acidic nature isn’t the best thing for your teeth, or you can brush your teeth more often to remove the potential problem.
Apple cider vinegar taken with the lemon juice or separately is reported to be capable of performing in the same manner as lemon juice.
Keep in mind that, as far as I know there is no scientific evidence which supports this idea even though many doctors as well as patients testify to its success.