Insulin, Serum/Plasma — Challenge Test, Substance Concentration
Measures the amount of insulin in blood during a glucose challenge, showing how effectively the body responds to rising blood sugar.
["This test helps evaluate how the pancreas releases insulin in response to glucose."]
Key facts at a glance
- LOINC
- 25693-3
- Short code
- Insulin sp3 p chal SerPl-sCnc
- Synonyms
- Insulin sp3 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 blood test measures insulin, a hormone made by the pancreas that helps glucose enter cells for energy. When performed as a challenge test, insulin is measured at specified times before and after glucose is given.
Why might I need this test?
A clinician may order this test to evaluate how the body handles glucose, investigate unusual blood sugar results, or assess the pancreatic insulin response. It may be used in the evaluation of diabetes, insulin resistance, or symptoms suggesting excess or insufficient insulin.
How is the test performed?
Blood is collected from a vein, usually from the arm. For a glucose challenge, glucose is given by mouth, and blood samples are collected at the times specified by the testing laboratory or healthcare professional.
How do I prepare for the test?
Follow the instructions provided for the challenge, including any fasting requirement and the exact time of each blood draw. Tell the healthcare team about medicines that contain insulin or affect blood sugar, and do not change medicines unless instructed.
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.
An unexpectedly high insulin response may occur with insulin resistance or conditions that cause excess insulin production. A low response may indicate that insulin production is insufficient. Results must be interpreted with glucose measurements, symptoms, medical history, and medicines, so a clinician should explain what the findings mean for you.
Short name
Insulin
Frequently asked questions
Does this test check for diabetes?
Do I need to fast before this test?
What medicines could affect the result?
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