Fasting blood glucose 7.9mmol/L is not necessarily to take medication. The normal range of fasting blood glucose is 3.9~6.1mmol/L. If the fasting blood glucose is 7.9mmol/L, it belongs to high and reaches the standard of diagnosing diabetes mellitus (fasting blood glucose is greater than or equal to 7mmol/L). In this kind of case, it is recommended to improve the glucose tolerance test and other tests, combined with the clinical symptoms, to determine whether diabetes mellitus occurs or not. Once diabetes is diagnosed, if the blood sugar cannot be controlled well through diet control and proper exercise, then we need to consider medication, which includes oral hypoglycemic drugs, such as metformin, acarbose, etc., as well as injectable insulin therapy. Therefore, a fasting blood sugar of 7.9 mmol/L does not necessarily require medication. In the case of abnormal fasting blood sugar, it is recommended to go to the hospital and ask the doctor to make a judgment.