Skip to content

Postprandial (2-hour) Glucose and Fructosamine Serum Test

Published: August 9, 2026Updated: August 16, 2026

This test measures your blood glucose level 2 hours after eating and evaluates long-term sugar control through fructosamine, a protein-bound form of glucose.

Quick summary

["It helps assess how well your body manages blood sugar both shortly after meals and over time."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
51769-8
Short code
Glucose 2h p fructose PO SerPl-mCnc
Synonyms
Glucose 2h 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 diabetes or prediabetes to check how your body handles glucose after eating. It can also help monitor treatment effectiveness or detect issues like poor insulin function.

What to Expect Before the Test

No special preparation is needed. You’ll provide a blood sample, usually drawn from your arm. If you’re fasting for another test, follow your doctor’s instructions.

What the Results Mean

The glucose test shows your immediate blood sugar response after eating, while fructosamine reflects average sugar levels over the past 2–3 weeks. Together, they give a clearer picture of your blood sugar control.

Common Causes of Abnormal Results

High results may indicate poor glucose tolerance, diabetes, or conditions affecting insulin use. Low results could suggest hypoglycemia or overactive insulin secretion.

Reference range

Fasting: 70-100 mg/dLN/A

Specimen: serum

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.

Clinical significance: This test is particularly useful for diagnosing or managing diabetes and related metabolic disorders. Elevated fructosamine may signal chronic hyperglycemia, while abnormal glucose levels post-meal can reveal delayed digestion or insulin resistance.

Frequently asked questions

What does a high fructosamine level mean?
A high fructosamine level suggests your blood sugar has been consistently elevated over the past few weeks, which may indicate uncontrolled diabetes or poor glycemic management.
Why is my glucose level checked 2 hours after eating?
This timing helps assess how your body processes glucose after a meal, which can reveal delayed digestion, insulin resistance, or other metabolic issues that standard fasting tests might miss.
Can I eat before this test?
Yes, you can eat normally before this test. It’s not a fasting test, so food won’t affect the glucose measurement, but follow any other test-specific instructions your doctor provides.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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