Some people with impaired glucose tolerance may have symptoms such as excessive drinking, excessive urination, and increased eating and drinking, but they may also have no specific symptoms and can only be detected by examination. Impaired glucose tolerance refers to a state in which blood glucose is higher than normal, but has not yet reached the diagnostic criteria for diabetes mellitus, which needs to be diagnosed by a glucose tolerance test because clinical symptoms may be less obvious at this time. Fasting blood glucose less than 7.0 mmol/L, but 2-hour post glycemic load blood glucose greater than or equal to 7.8 mmol/L less than 11.1 mmol/L, suggests impaired glucose tolerance. A small number of people may experience symptoms such as thirst, increased urination, hyperphagia, and itchy skin due to elevated blood glucose. It is recommended that impaired glucose tolerance should be treated with prompt lifestyle interventions, limiting daily calorie intake and being physically active to reduce the risk of diabetes. Medications such as metformin should be taken on medical advice if necessary.