Glucose tolerance generally refers to the glucose tolerance test, as long as the standardization of the test process, you can ensure the accuracy of the results, you can pass the test at once. Three days before the oral glucose tolerance test, you need to ensure that the daily dietary sugar content should be more than 150g, the night before the test should be fasted for at least 8~10 hours, keep fasting state until the next morning, take blood tests to detect the concentration of blood glucose and then take glucose (adults need to take 75 grams of anhydrous dextrose, and children need to be calculated according to the 1.75g per kilogram, but the total amount should be less than 75g). After taking glucose, blood glucose concentration needs to be measured at one hour, two hours and three hours respectively, during which it is not recommended to drink a lot of water so as not to affect the accuracy of the test results. However, a second test is required if necessary in the event of abnormal blood glucose values. If the glucose tolerance test results are abnormal, it is recommended to go to the endocrinology department of the hospital.