Insulin, Serum/Plasma — 5th Post-Challenge Specimen, Mass Concentration
Measures insulin in the fifth timed blood sample after a challenge, usually a glucose load, to assess how the body responds to glucose.
["This timed insulin measurement helps evaluate insulin release after a glucose challenge."]
Key facts at a glance
- LOINC
- 12742-3
- Short code
- Insulin sp5 p chal SerPl-mCnc
- Synonyms
- Insulin sp5 p chal SerPl-mCnc
- 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 serum or plasma. It is typically collected as the fifth timed specimen after a challenge, often during a glucose tolerance test.
Why might I need this test?
The test helps assess how effectively the body releases insulin in response to glucose. It may be used in evaluating diabetes, insulin resistance, or episodes of low blood sugar and is usually interpreted with the glucose results from the same challenge.
How is the test performed?
A blood sample is drawn and analyzed for insulin. During a glucose challenge, blood is collected at specified times before and after you drink a glucose solution.
How do I prepare for the test?
Follow the timing and fasting instructions provided by your healthcare professional. Do not stop medicines or supplements unless your clinician specifically tells you to, because medications can affect insulin and glucose results.
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 insulin levels may occur with insulin resistance, obesity, type 2 diabetes, or the use of insulin medication. Lower levels may occur when the body does not produce enough insulin or when insulin is being administered. A delayed or exaggerated insulin response after a glucose challenge can suggest difficulty regulating blood sugar, so results are interpreted together with glucose levels, symptoms, medications, and the collection timing.
Short name
Insulin (5th post-challenge sample)
Frequently asked questions
Does one insulin result diagnose diabetes?
What is the fifth post-challenge sample?
Can insulin medicines affect 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