There are many reasons for stone formation, which may be caused by metabolic abnormalities, urinary tract obstruction, drugs, improper diet and other factors. 1. Abnormal metabolism: when the patient’s body metabolism is abnormal, resulting in urine acidity and alkalinity exceeding the normal range, which can lead to the deposition of different ions and compounds, forming various types of stone crystals. Or it may be caused by hypercalcemia, hypercalciuria, hyperoxaluria and other diseases. 2. Urinary tract obstruction: Urinary tract obstruction can lead to crystals or matrix located in poor drainage sites, urine retention will be secondary to urinary tract infection, which can induce stone formation. 3. Drugs: If the patient takes aminopterin, magnesium silicate, sulfonamides, or the use of vitamin C, vitamin D, acetazolamide and other drugs, may induce stone formation. 4. Improper diet: If the diet contains more animal protein and less fiber, it may lead to the formation of upper urinary tract stones. Or if you drink less water and urinate less, you may increase the concentration of salts and organic substances and develop stones. There are many reasons for the formation of stones, and patients are advised to go to a regular hospital, identify the cause of the disease and undergo early treatment.