Hello dear I understand your concern Stone in the urinary tract produce pain and blood in the urine. nonobstructing mean it does not obstruct the urinary tract so it does not produce hydronephrosis and kidney infection. It is small in size and pass in the urine. But it may produce pain due to ureteric muscle contraction and damage the wall of ureter and bladder cause blood in urine. If still is there it could be treated by the medicine like diuretcs, Drink plenty of water and fruit juice of the cranberry, orange and pineapple. Take antispasmodic like diclycomine and pyridium for the pain. Hope this may help you Contact HCM for further health query Best regards Dr. Sagar