Insulin concentration in serum (2-hour post-glucose challenge)
This test measures your insulin levels after drinking a glucose solution to help assess how your body responds to sugar. It’s often used in diabetes screening or evaluation of insulin sensitivity.
["This test helps doctors check if your pancreas produces enough insulin after eating sugar."]
Key facts at a glance
- LOINC
- 1564-4
- Short code
- Insulin 2h p 75 g Glc PO SerPl-mCnc
- Synonyms
- Insulin 2h p 75 g Glc PO SerPl-mCnc
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 2.6
- Ref high
- 24.9
- Fasting
- true
- 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 (like frequent urination, extreme thirst, or unexplained weight changes) or if you’re at risk for diabetes (e.g., obesity, family history, or high blood pressure). It can also be used to monitor how well diabetes treatments are working.
How the Test Works
You’ll drink a sugary liquid, and your blood will be drawn two hours later to check insulin levels. This helps doctors see how your body handles glucose and insulin over time.
What to Expect Before the Test
No special preparation is needed, but avoid eating or drinking anything except water for 10 hours before the test. Wear comfortable clothes and bring your doctor’s contact info.
What to Expect During the Test
A healthcare provider will draw blood from a vein in your arm. You may feel a slight pinch, but it’s quick. You can sit or lie down during the procedure.
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.
Low insulin levels after glucose intake may indicate insulin resistance or diabetes, while very high levels could suggest overproduction of insulin (e.g., from tumors or other conditions). This test helps diagnose or manage diabetes and related metabolic disorders.
Short name
2-hour Insulin Level
Frequently asked questions
How long does this test take?
Will I need to fast before this test?
What if I have diabetes and need 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