Specimen Requirements

Consult Billings Clinic Laboratory at 866-232-2522 for pediatric doses.

Serum or plasma should be physically separated from cells as soon as possible with a maximum limit of two hours from the time of collection.

1. Draw blood in a green-top (lithium heparin) tube(s) or a red-top tube (serum) from a fasting patient.
2. Have adult patient drink entire glucose tolerance beverage supplied. Ingestion should be completed within 10 minutes. The timing starts at this point.
3. Draw specimen as above at 1 hour and 2 hours after ingestion of the dose.
4. During time of draw, patient must not eat or drink, with exception of plain water.
5. They may be given ice chips to moisten mouth.
6. Spin down each specimen, separate plasma or serum from cells as soon as possible after draw, and send 1 mL of heparinized plasma or serum.

• It is suggested that patient follow a special high carbohydrate (150-300 g) diet for 3 days prior to this test unless otherwise directed by the physician.
• Glucose solution will not be given to patients with fasting glucose = 150 mg/dL without notification and consent of physician.
• Vomiting negates test.
• Label specimens appropriately (timed interval).

DO NOT FREEZE