Glucose tolerance test is Oral Glucose Tolerance Test (OGTT). Generally, you don’t need to bring your own cups, but the hospital will provide disposable paper cups. The hospital will provide you with disposable cups. Just follow your doctor’s instructions when doing the test. To prepare for the OGTT, you should not eat any food or drink any water for 8 to 10 hours, and keep fasting state in the early morning, and during the test, you should not drink tea or coffee, prohibit smoking, and do not engage in strenuous exercise. Adults were given 75g of anhydrous glucose orally, dissolved in 250-300ml of water, and drank up in about 5 minutes. Counting from the first sip, 30 minutes, 1 hour, 2 hours, and 3 hours, forearm blood collection is performed to determine blood glucose level. The OGTT is commonly used in patients whose blood glucose is elevated above the normal range, but who do not meet the criteria for a diagnosis of diabetes. Certain medications such as glucocorticoids, prolonged bed rest, and smoking may affect the results of the test. Patients who need to have a glucose tolerance test should go to the hospital early in the morning on an empty stomach and follow the doctor’s instructions.