Glucose in Serum or Plasma (Concentration)
This test measures the amount of glucose (sugar) in your blood drawn from a vein. It helps assess how well your body is managing blood sugar levels.
["This test helps monitor blood sugar control, often used in diabetes management or before certain procedures."]
Key facts at a glance
- LOINC
- 2357-2
- Short code
- G6PD RBC-cCnc
- Synonyms
- G6PD RBC-cCnc
- Category
- glucose
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Ref low
- 4.2
- Ref high
- 5.9
- Critical range
- 2 N/A – 7 N/A
- Fasting
- true
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 85041
- SNOMED
- 900000000000003001
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
Why This Test Is Done
Your healthcare provider may order this test to check for diabetes, monitor diabetes treatment, diagnose conditions like hypoglycemia (low blood sugar), or evaluate metabolic health before surgeries or other medical procedures.
What to Expect Before the Test
You may be asked to fast for 8–12 hours before the test, depending on your doctor’s instructions. Bring any medications you’re taking, as some may affect results. Avoid smoking or chewing gum right before the draw.
How the Test Is Performed
A healthcare professional will insert a small needle into your arm to draw blood. You may feel a slight prick, but it usually doesn’t cause pain. The blood sample is sent to a lab for analysis.
What the Results Mean
Results are typically reported as a numeric value (e.g., mg/dL or mmol/L), but your doctor will interpret them in the context of your overall health. Abnormal results may trigger further testing or adjustments to treatment.
Reference range
Adult males: 4.2-5.9; Females: 3.8-5.1 x 10^12/LN/A
No special preparation required. Stay well hydrated.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
High glucose levels may indicate diabetes, prediabetes, or other metabolic disorders. Low levels can signal hypoglycemia, which may require immediate medical attention. Regular monitoring helps prevent long-term complications like nerve damage or heart disease.
Short name
Serum/Plasma Glucose
Frequently asked questions
Will fasting be required for this test?
Can I take my usual medications before the test?
What if my blood sugar is very high or very low?
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