2 hours
Test Updated:
GLUC3
OGTT
3 Hour Gluocose Tolerance
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Test Overview
Hexokinase, NADH Endpoint
Determine glucose level, monitor insulin therapy, evaluate carbohydrate metabolism.
Fasting <95 mg/dL; 1 hr <180 mg/dL; 2 hr <155 mg/dL; 3 hr <140 mg/dL. A positive diagnosis results from a fasting value equal to or above 95 mg/dL or any two or more values that are equaled or exceeded.
* Reference ranges may change over time. Please refer to the original patient report when evaluating results.
Specimen Requirements
Collect blood in an SST tube from a fasting patient. Administer 100 gm Glucola. Instruct patient to finish drinking the Glucola within 5 minutes of the time he or she starts drinking and not to eat anything except a few sips of water after finishing the Glucola. The patient should remain seated and not smoke throughout the test. Collect blood in an SST tube exactly 1, 2 and 3 hours after the patient finished drinking the Glucola. Centrifuge, aliquot serum into plastic vials and refrigerate. Label vials appropriately (Fasting, 1 HR, 2 HR, and 3HR).
Collect blood in an SST tube from a fasting patient. Administer 100 gm Glucola. Instruct patient to finish drinking the Glucola within 5 minutes of the time he or she starts drinking and not to eat anything except a few sips of water after finishing the Glucola. Collect blood in an SST tube exactly 1, 2, and 3 hours after the patient finished drinking the Glucola. Centrifuge within 4 hours of collection, aliquot serum into a plastic vial and refrigerate. If specimen cannot be centrifuged at client site, please arrange for delivery to MLabs within 3 hours of specimen collection. Label vials appropriately (Fasting, 1 HR, 2 HR, and 3HR).
