I take back my prior comment because urea really is a diuretic in effect, so there is a possibility of it working in theory to relieve a small stone. Even so, t

I take back my prior comment because urea really is a diuretic in effect, so there is a possibility of it working in theory to relieve a small stone. Even so, the urine should probably first be checked for normalcy via a urine test strip. In practice, during a stone, urine is often mixed with blood, and the combination would be utterly strange to drink. These days we have pharmaceutical diuretics, but one has to have procured them ahead of time because no doctor here will give you one to pass a stone. They would prefer to bill you instead for an expensive lithotripsy procedure which also gives you a lot of radiation via fluoroscopy.