Glucose, Serum or Plasma Concentration
This test measures the amount of glucose (sugar) in your blood drawn from either your vein (serum/plasma). It helps assess how well your body is managing blood sugar levels.
["A glucose test checks your blood sugar, important for managing diabetes or other metabolic conditions."]
Key facts at a glance
- LOINC
- 45056-9
- Short code
- Glucose 8 PM SerPl-sCnc
- Synonyms
- Glucose 8 PM SerPl-sCnc
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 70
- Ref high
- 100
- Critical range
- 50 N/A – 400 N/A
- Fasting
- true
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 82947
- SNOMED
- 260395008
- 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 healthcare provider may order this test to monitor blood sugar levels, diagnose diabetes or prediabetes, check for low blood sugar (hypoglycemia), or evaluate conditions affecting sugar metabolism, such as liver or kidney disease. It can also be used during pregnancy to screen for gestational diabetes or to assess response to treatments like insulin.
What to Expect Before the Test
No special preparation is usually needed, but you may be asked to fast (not eat or drink anything except water) for 8 to 12 hours before the test if it’s a fasting glucose check. If you’re not fasting, you can eat and drink normally. Let your provider know about any medications you’re taking, especially those that might affect blood sugar.
How the Test Is Performed
A healthcare professional will insert a small needle into a vein in your arm or hand to draw blood. You may feel a slight pinch or sting, but it usually doesn’t cause much discomfort. The blood is then sent to a lab for analysis.
What the Results Mean
Results are typically reported as a concentration of glucose in the blood. While specific ranges vary by lab and clinical context, your results will be compared to standard reference values provided by your healthcare team to determine if your blood sugar is within a healthy range or if further action is needed.
Reference range
Fasting: 70-100 mg/dLN/A
Fasting for 8-12 hours required. Water is permitted. Avoid chewing gum and smoking before the test.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
High glucose levels can indicate diabetes, poor blood sugar control, or other metabolic disorders. Low glucose levels may signal hypoglycemia, which can cause dizziness, confusion, or weakness. Regular monitoring helps prevent complications like nerve damage, heart disease, or kidney problems. Your provider will discuss results in the context of your overall health and treatment plan.
Short name
Glucose Level
Frequently asked questions
What causes abnormal glucose levels?
How can I manage my glucose levels at home?
Can lifestyle changes alone fix high or low glucose levels?
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