Insulin concentration in serum (fasted state)
This test measures the amount of insulin in your blood after you’ve fasted for a certain period. It helps assess how your body produces and responds to insulin.
["Insulin levels help diagnose conditions like diabetes or check how well your pancreas is working."]
Key facts at a glance
- LOINC
- 50867-1
- Short code
- Insulin Fld-sCnc
- Synonyms
- Insulin Fld-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 Is This Test Done?
Your doctor may order this test if they suspect diabetes, prediabetes, or other hormone-related conditions. It can also be used to evaluate insulin resistance or to monitor treatment for conditions affecting insulin production.
What to Expect Before the Test
You’ll need to fast (not eat or drink anything except water) for 8 to 12 hours before the test. Avoid smoking or taking certain medications that could affect insulin levels. Your blood will be drawn from a vein, usually in your arm.
How the Test Works
A sample of your blood is taken and analyzed to measure insulin concentration. The test uses a specialized immunoassay method to detect insulin in your serum.
What the Results Mean
Results help determine if your insulin production is normal or if there’s an imbalance that could affect blood sugar levels. Your doctor will interpret the results in the context of your overall health and symptoms.
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: Insulin levels can indicate whether your body produces enough insulin to regulate blood sugar properly. Low levels may suggest conditions like diabetes or pancreatic issues, while abnormal spikes could indicate metabolic disorders or other endocrine problems.
Frequently asked questions
What does a normal insulin level mean for me?
How long will I need to fast before the test?
Can I take my usual medications 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