Drinking water before the kidney function test may have an effect on the test results, and the results obtained may be less accurate, but it needs to be decided according to the amount of water drunk, if the amount of water drunk is very small, the effect on the kidney function test is minimal, if the amount of water drunk is relatively large, it may affect the test results. Kidney function test mainly includes creatinine, urea nitrogen, uric acid, bicarbonate concentration, etc. Drinking water has an effect on the measurement results. Drinking a large amount of water before the test will make the blood dilute, which in turn will make the content of these substances in the blood decrease, making the results lower than the actual value, which in turn will affect the assessment of the condition. Therefore, when it is necessary to carry out kidney function tests, try to avoid drinking water, and if the test results are abnormal, you should consult your physician to clarify the cause of the disease and carry out standardized treatment under the guidance of the doctor.