Insulin Glucose Tolerance Test

Orderable EAP code:

LAB00605

Billable EAP Codes:

80001741 x 1 (Fasting)
80001740 x 1 (Tube 1)
80001735 x 1 (Tube 2)
80001736 x 1 (Tube 3)
80001737 x 1 (Tube 4)
80001738 x 1 (Tube 5)
80001739 x 1 (Tube 6)
80001732 x 1 (Tube 7)
80001733 x 1 (Tube 8)
80001734 x 1 (Tube 9)

CPT Codes:

82947 x 10

Lab Section:

Core Lab

Turnaround Time:

Routine: 2 Hours
Urgent: 1 Hour

Test Schedule:

24 hours, 7 days a week.

Units:

mg/dL

Specimen Requirements:

2 mL blood in a GRAY top tube.

Reference Range:

See comments.

Comments:

The patient must fast overnight prior to the Insulin Tolerance Test. Insulin is injected intravenously corresponding to 0.1 unit per kg of body weight. Collect blood samples for glucose at fasting, 15 minutes, 30 minutes, 45 minutes, 1 hour, and 90 minutes. Normally, the 30-minute blood glucose value is about 50% of the fasting level and by 90 minutes the glucose level returns to the fasting level.

Specimen Stability: up to 24 hours at room temperature.

Synonyms:

Glucose Tolerance
GTT
ITT