3-hour Glucose Tolerance Blood Test
Test Code: 090365
Specimen Type: Blood
3-hour Glucose Tolerance Blood Test (Labcorp)
The 3-hour glucose tolerance test is used to determine how well a person's body processes glucose. Glucose is the sugar the body uses for energy. This test is designed to measure how quickly glucose is cleared out of the body over a period of time by measuring glucose levels in blood samples taken at regular intervals after the ingestion of a glucose solution. This type of testing is typically done to aid in the diagnosis of type 2 diabetes.
A glucose tolerance test is typically ordered when someone is believed to be at risk for diabetes. This test provides more information than a 2-hour glucose tolerance test by measuring additional blood samples.
Turnaround for the Glucose Tolerance 3-Hour Test is typically 1-2 business days.
Where can I find a 3 Hour Glucose Tolerance test near me?
Check our lab finder to locate a collection site in your area.
Note: Result turn around times are an estimate and are not guaranteed. Our reference lab may need additional time due to weather, holidays, confirmation/repeat testing, or equipment maintenance.
People taking this test should be active and eat a regular diet that includes at least 150 grams of carbohydrate daily for three days prior to the test.
Fasting should be observed prior to collection for 8-14 hours.
It is advised to discontinue, whenever possible, all nonessential medication that can affect glucose metabolism at least three days before testing. Please consult your doctor regarding any medications and how they may affect this test.
This test requires four blood draws. The first will be taken when you arrive at lab. You will then be given a glucose solution to drink. 3 subsequent collections will be taken at 1 hour intervals. You will be required to remain at the lab until the final collection is taken.
The blood draws for this test can also be taken at half hour intervals if requested.
Please note the business hours for your selected lab location when determining when to come to the lab. Once the collection process has begun you will be required to remain at the lab for 3 hours. Be aware if the lab takes a break for lunch and make sure to arrive more than 3 hours prior to this time.