Ordering Recommendation

Use to diagnose gestational diabetes mellitus, diabetes mellitus, or impaired glucose tolerance.

New York DOH Approval Status

This test is New York state approved.

Specimen Required

Patient Preparation

Patient should fast for at least eight hours prior to collection of fasting specimen.


Collect 2 timed specimens (fasting and 120 minutes). Gray (sodium fluoride/potassium oxalate). Collect separate tube for each timed specimen.

Specimen Preparation

Separate plasma from cells and refrigerate within 2 hours of collection. Transfer 1 mL plasma per time point to individual ARUP Standard Transport Tube. (Min: 0.2 mL/time point)

Storage/Transport Temperature


Unacceptable Conditions

After separation from cells: Ambient: 24 hours; Refrigerated: 1 week; Frozen: 1 year


Quantitative Enzymatic Assay




Within 24 hours

Reference Interval

Glucose (fasting and 120 min). Interpretation available on consultation with medical director.

Interpretive Data

Interpretive limits for glucose tolerance testing vary based on population, glucose dose, and time of collection after glucose administration.  Published guidelines from the American Diabetes Association or the American Congress of Obstetricians and Gynecologists should be consulted for interpretive values.

Compliance Category



Administer 75 g glucola. Do not mix with water unless directions on product label indicate to do so. The patient should be fasting for at least eight hours prior to start of test, should remain inactive, and receive nothing by mouth (including tobacco) during test period.  A small sip of water or ice is permissible. Reasons for invalid results include emesis and conditions which delay stomach emptying.

Hotline History


CPT Codes

82947; 82950


Component Test Code* Component Chart Name LOINC
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.


  • Blood Glucose
  • Blood Sugar
  • Fasting Blood Glucose
  • Fasting Blood Sugar
  • Fasting Plasma Glucose
  • FBG
  • FBS
  • FPG
  • GLU
  • GTT
  • OGTT
  • Oral Glucose Tolerance Test
Glucose Tolerance Test