Usually it is done by giving the patient a liquid that is sugar rich and then after an hour the blood is drawn to check for glucose levels .If the levels are 140mg/dl then it is normal if it is more then you need to consult a doctor.
If you had a fasting blood glucose test, a level between 70 and 100 mg/dL (3.9 and 5.6 mmol/L) is considered normal. If you had a random blood glucose test, a normal result depends on when you last ate.
Random glucose testing measures a person's blood glucose levels at any given point in the day.
If you had a fasting blood glucose test: A level of 100 to 125 mg/dL (5.6 to 6.9 mmol/L) means you have impaired fasting glucose. Consult a doctor to reverse your condition.
You come under the category prediabetes one should consult a doctor to reverse prediabetes.
Random glucose testing measures a person's blood glucose levels and if it is found less than 140mg/dl then it is normal.