What are common causes of kidney stones?
The crystals that lead to kidney stones are likely to form when your urine contains a high concentration of certain substances — especially calcium, oxalate, uric acid and rarely, cystine — or low levels of substances that help prevent crystal formation, such as citrate and magnesium. Crystals also may form if your urine becomes too concentrated or is too acidic or too alkaline. A number of factors can cause changes in your urine, including the effects of heredity, diet, drugs, climate, lifestyle factors and certain medical conditions.