The pain strikes in waves in the lower back or right on the side of the trunk, around the bottom rib. Often, it's accompanied by sweating, vomiting and nausea, blood in the urine and the urgent need to go to the bathroom. That generally happens within a day or two of the onset of pain, bringing relief to the stones' unwary hosts. Kidney stones usually form in the center of the kidney, on the ends of collecting tubules. That's where the kidney drains out its wastes into tiny tubes, which lead down into the ureter and finally into the bladder.
Little stones can break off and leave the body easily in urine.
But bigger stones can irritate the ureter and get stuck as they move toward the bladder, prompting that infamous pain and interfering with urine flow. The stones form when certain natural chemicals in urine crystallize and the crystals clump together. Calcium is the culprit in most cases of kidney stones, Huffman says. Many stones are caused by metabolic problems or the way the body deals with foods or drinks in the diet, such as tea. Uric acid, phosphate and other substances also may cause stones.