Glucose and Fructose Measurement in Serum/Plasma (15-Hour Postprandial)
This test measures your blood sugar (glucose) and fructose levels after eating for 15 hours. It helps assess how your body handles glucose over time, especially useful for diagnosing conditions like diabetes or metabolic disorders.
["This test helps doctors check how well your body manages blood sugar after prolonged eating."]
Key facts at a glance
- LOINC
- 51767-2
- Short code
- Glucose 1.5h p fructose PO SerPl-mCnc
- Synonyms
- Glucose 1.5h p fructose PO SerPl-mCnc
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 70
- Ref high
- 100
- Critical range
- 50 N/A – 400 N/A
- Fasting
- true
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82947
- SNOMED
- 260395008
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Doctors may order this test if you have symptoms of high blood sugar (like frequent urination, extreme thirst, or fatigue), if you have a family history of diabetes or metabolic issues, or if you’re being evaluated for conditions like fructose intolerance or glucose metabolism disorders. It can also be used to monitor treatment progress in certain cases.
What to Expect Before the Test
You’ll need to fast for 15 hours before the test, meaning no food or drink (except water) after midnight the night before. Bring any medications you’re currently taking, as some may need to be adjusted or taken separately. Wear comfortable clothing for the blood draw.
What Happens During the Test
A healthcare provider will take a blood sample from a vein in your arm. This is usually quick and painless, though you may feel a slight pinch. The sample is then sent to a lab for analysis using a specialized method to measure both glucose and fructose levels.
What the Results Mean
Results show your blood sugar and fructose levels at a specific time point after eating. High glucose levels may indicate diabetes or insulin resistance, while abnormal fructose levels could suggest metabolic issues or dietary sensitivities. Your doctor will interpret these results in the context of your overall health.
Reference range
Fasting: 70-100 mg/dLN/A
Fasting for 8-12 hours required. Water is permitted. Avoid chewing gum and smoking before the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
This test is particularly useful for identifying delayed glucose responses, which can be overlooked by standard fasting tests. Elevated glucose or fructose levels may signal underlying metabolic disorders, such as fructose malabsorption or impaired glucose metabolism, that require further medical evaluation or dietary adjustments.
Short name
15-Hour Post-Meal Blood Sugar Test
Frequently asked questions
How long does it take to get my results?
What should I do if I miss my fasting window?
Can I take my diabetes medication before this test?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy