Oral Glucose Tolerance Test

For Oral Glucose Test, the patient is asked to fast for about 10-16 hours preferably overnight. However, one can
consume water during the fasting. The next morning, a blood sample is collected and analyzed to give a baseline reading. This is the initial test and the patient is asked to drink a liquid with 75 g of glucose content within 5 min.
Once the glucose water in ingested and absorbed into the bloodstream, another blood test is taken approximately after 30 minutes. Similarly tests will be continued after duration of 1, 2 and 3 hours of drinking glucose water. Each of the 5 tests helps to determine how the body responds to the sugary liquid. It is extremely important to take the test after fasting.
The 5 tests will display the fluctuating blood sugar levels in the body over time. For a non-diabetic person, the levels will spike and quickly drop down to normal, however for a person with diabetes; the level will escalate and fall in a slower rate.

A person should remain seated for the duration of test and do not smoke until the test is completed. Even drinking black coffee or smoking a cigarette can affect the levels drastically.