Insulin concentration (serum/plasma) measured 15 hours post-glucose challenge
This test evaluates how your body processes insulin after consuming glucose. It helps assess insulin sensitivity and potential diabetes-related issues.
["Measures insulin levels 15 hours after a glucose challenge to check insulin sensitivity."]
Key facts at a glance
- LOINC
- 55489-9
- Short code
- Insulin 1.5h p Gc SerPl-sCnc
- Synonyms
- Insulin 1.5h p Gc SerPl-sCnc
- Category
- hormone
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 2.6
- Ref high
- 24.9
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 83525
- SNOMED
- 413618004
- 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
Your doctor may order this test if you have symptoms of diabetes, insulin resistance, or unexplained weight changes. It can also help diagnose conditions like Cushing’s syndrome or other hormonal imbalances that affect insulin metabolism.
What to Expect Before the Test
You’ll fast overnight before the test. On the test day, you’ll drink a glucose solution, and your blood will be drawn 15 hours later to measure insulin levels. No special preparation is needed beyond fasting.
What the Results Mean
Higher-than-expected insulin levels may indicate insulin resistance or overproduction of insulin, while lower levels could suggest insufficient insulin production or metabolic issues.
Common Conditions Linked to This Test
This test helps diagnose or monitor conditions like type 2 diabetes, prediabetes, insulinoma (a rare tumor producing excess insulin), or other metabolic disorders affecting glucose and insulin balance.
Reference range
Fasting: 2.6-24.9 μIU/mLN/A
No special preparation usually required. Stay well hydrated. Inform your healthcare provider of all medications and supplements you are taking.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical significance: Elevated insulin levels post-glucose challenge may signal insulin resistance or hyperinsulinemia, while abnormal results can guide treatment for diabetes, metabolic syndrome, or endocrine disorders.
Short name
15-Hour Insulin Post-Glucose Challenge
Frequently asked questions
How is this test different from a standard fasting insulin test?
Will I need to take any special medications before the test?
Can I eat or drink anything after the glucose drink?
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