A glucose tolerance test measures how well your body’s cells are able to absorb glucose, or sugar, after you ingest a given amount of sugar.
1. Patient should be instructed to have nothing to eat or drink for at least 8 hours before the test (except for sips of water).
2. Patient should be instructed to refrain from smoking and drinking coffee just before and during test.
3. Draw blood specimen for a fasting glucose.
4. After drawing fasting specimen, give the patient a 75 g dose of glucose (patient must drink entire beverage within 5 minutes).
5. Draw blood specimens at 1 hour, 2 hour, 3 hour and 4 hours post glucose ingestion.