Stone 0.4cm is not big. For stones less than 0.5cm, you can effectively expel the stones from the body through conservative treatment. It is recommended to drink 2000ml of water every day, which can form more urine and effectively promote the discharge of stones. Take stone removal medication every day, commonly used are stone removal granules, kidney stone pass, urinary stone pass, and Wulianhua stone pill. Take alpha-blockers, which effectively diastasize the ureter and have a dilation effect, which can promote stone discharge. Usually, you should take more exercise, such as jogging, stairs, and skipping rope, which can expel stones quickly through these treatments.