Glucose tolerance test is known as oral glucose tolerance test, and its testing process is mainly to measure the blood glucose level after taking glucose orally, but you need to pay attention to fasting and so on before the test. 1.Test process (1) Take a certain amount of glucose water orally within five minutes after fasting for 8~10h. (2) Starting from the first sip of glucose water, measure the venous blood glucose before taking glucose water, 30 minutes, 1h, 2h and 3h after taking glucose respectively. 2. Preparation of glucose water: 75g of anhydrous glucose powder can be used, dissolved in 250-300ml of water to make sugar water. 3. Interpretation of test results: When fasting blood glucose ≥7.0mmol/L before taking glucose water, or blood glucose ≥11.1mmol/L after taking glucose water for 2h, it can be used as a basis for diagnosis of diabetes mellitus. 4.Precautions (1) It is recommended to avoid strenuous exercise during the test. (2) During the test, avoid drinking tea and coffee, and do not smoke. (3) Eat normally three days before the test and avoid dieting. If there is any abnormality in the test, it is recommended to go to the hospital in time.