Glucose in Serum or Plasma (Quantitative)
This test measures the amount of glucose (sugar) in your blood, typically drawn from a vein or fingerstick.
["A glucose test helps check for blood sugar levels, often used in diabetes management or general health assessments."]
Key facts at a glance
- LOINC
- 1628-7
- Short code
- GH 1h p 1 g/kg Glc PO SerPl-mCnc
- Synonyms
- GH 1h p 1 g/kg Glc PO SerPl-mCnc
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- true
- 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 to monitor blood sugar levels, diagnose conditions like diabetes, evaluate metabolic health, or assess for complications such as hypoglycemia (low blood sugar) or hyperglycemia (high blood sugar). It can also be part of routine check-ups or during pregnancy.
How the Test Works
A small sample of blood is collected and analyzed to determine the concentration of glucose. The test measures how much sugar is present in your blood at the time of the draw.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast (not eat or drink) for 8–12 hours before the test if it’s part of a fasting glucose study. If fasting isn’t required, you can eat and drink normally.
What to Expect During the Test
The test involves a quick blood draw from a vein in your arm or, less commonly, a fingerstick. You may feel a slight pinch, but it usually takes only a few seconds. The blood is then sent to a lab for analysis.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Abnormal glucose levels can indicate diabetes, insulin resistance, or other metabolic disorders. High levels may signal prediabetes or diabetes, while very low levels can be dangerous and require immediate medical attention. Regular monitoring helps manage long-term health risks and prevents complications.
Short name
Serum/Plasma Glucose
Frequently asked questions
How often should I get this test?
What do my results mean?
Can I eat or drink 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