Insulin, Serum/Plasma — 1-Hour Post-Challenge, Substance Concentration
Measures insulin in blood drawn 1 hour after a challenge, usually a glucose load, to assess how the pancreas responds to rising blood sugar.
["This timed insulin test helps evaluate pancreatic insulin production in response to a glucose challenge."]
Key facts at a glance
- LOINC
- 25686-7
- Short code
- Insulin sp11 p chal SerPl-sCnc
- Synonyms
- Insulin sp11 p chal 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
What is this test?
This test measures the amount of insulin in a blood sample collected 1 hour after a challenge, usually a glucose drink. Insulin is a hormone made by the pancreas that helps cells take up glucose for energy.
Why might I need this test?
A timed insulin test may be used to assess how effectively the pancreas releases insulin after glucose is given. It is sometimes used in the evaluation of diabetes, insulin resistance, or unusual blood sugar patterns.
How is the test performed?
A blood sample is drawn exactly 1 hour after the challenge. The sample is tested to determine the insulin concentration, and the result is interpreted along with blood glucose measurements and your clinical history.
How do I prepare for the test?
Follow the testing center's instructions about fasting and the challenge. Take medicines only as directed, and tell the staff if you are pregnant, have recently had illness, or have eaten before the test.
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.
Higher-than-expected insulin after the challenge may occur with insulin resistance, obesity, or prediabetes, especially when glucose is also elevated. Lower-than-expected insulin may indicate reduced pancreatic function or an inappropriately low insulin response. Results require interpretation alongside glucose levels, symptoms, medicines, and other tests.
Short name
Insulin, 1-Hour Post-Challenge
Frequently asked questions
Is this the same as a routine insulin test?
Why is my blood glucose measured at the same time?
Do I need to fast 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