[header] How to pass a kidney stone [title] Understand that some stones are easier to pass naturally than others. [step] How readily a stone responds to home treatment mostly depends on the size of the stone. [substeps] Home treatments are usually effective on stones less than 1/10-inch (3 mm). 
Once kidney stones reach about 3/10-inch (8 mm), they are only 20 percent likely to pass on their own with home treatment. Stones that are 2/5-inch (1 cm) almost always need professional medical treatment.