Oral Glucose Tolerance Test (OGTT) Method 1. Starting at 7-9 a.m., the subject should take 75g of anhydrous glucose powder dissolved in 300ml of water or 82.5g if using 1 molecule of water glucose, or 1.75g per kg of body weight for children, with the total amount not exceeding 75g. The sugar solution should be finished within 5 minutes. 2. Blood was collected from the forearm to measure blood glucose before and 2 hours after taking the first sip of sugar. 3.During the test, subjects should not drink tea and coffee, do not smoke, and do not do strenuous exercise, but they should not be absolutely bedridden. 4.Blood specimens should be sent for examination as soon as possible. 5.The daily carbohydrate intake should be not less than 150g within 3 days before the test. 6.Discontinue the use of drugs that may affect OGTT such as contraceptives, diuretics or phenytoin sodium for 3-7 days before the test.