Glucose in Serum or Plasma (24-hour Profile)
This test measures your blood glucose levels over a 24-hour period using a sample of your serum or plasma. It helps doctors assess how your body manages glucose, especially important for diagnosing or monitoring conditions like diabetes.
["Understanding how your body naturally regulates blood sugar over time."]
Key facts at a glance
- LOINC
- 40299-0
- Short code
- GH 1h p CLN SerPl-mCnc
- Synonyms
- GH 1h p CLN SerPl-mCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 0
- Ref high
- 17
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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 they suspect you have diabetes, prediabetes, or another condition affecting blood sugar control. It can also help evaluate how well medications or lifestyle changes are working to manage glucose levels.
What to Expect Before the Test
You’ll typically provide a blood sample (serum or plasma) at multiple time points over 24 hours, often including fasting and post-meal samples. Follow your doctor’s instructions carefully about diet, activity, and timing of samples to ensure accurate results.
How the Test Works
Blood is drawn from a vein (usually in your arm) and sent to a lab. The lab measures glucose concentration using a specialized method, often automated and precise, to detect small changes over time.
What the Results Mean
Results show your glucose levels at different times of day. Abnormally high or low levels may indicate issues like diabetes, hormonal imbalances, or other metabolic disorders. Your doctor will interpret these results in the context of your overall health.
Reference range
NCBI: NSE 0-17 ng/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.
This test is critical for diagnosing and managing diabetes and related conditions. It helps identify patterns in blood sugar that might not be apparent from a single fasting or random glucose measurement. For example, it can reveal whether you have reactive hypoglycemia or impaired glucose tolerance.
Short name
24-Hour Glucose Profile
Frequently asked questions
How often should I get this test?
What does a normal result mean?
Can I eat or drink before the 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 17, 2026. · Read our editorial policy