Skip to content

Glucose in Serum or Plasma (Mass Concentration)

Published: August 9, 2026Updated: August 16, 2026

This test measures the amount of glucose (sugar) in your blood, typically drawn from a vein or collected in a tube.

Quick summary

["Glucose levels help monitor blood sugar and identify diabetes or other metabolic conditions."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
14146-5
Short code
GH 1h p chal SerPl-mCnc
Synonyms
GH 1h p chal SerPl-mCnc
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
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 Is This Test Done?

Your healthcare provider may order this test to check for diabetes, monitor blood sugar control, diagnose hypoglycemia (low blood sugar), or assess conditions like kidney disease or liver problems. It’s also used in routine check-ups or during pregnancy.

How Is the Sample Collected?

A small needle will draw blood from a vein in your arm. The blood is placed in a tube and sent to the lab for testing. You may feel a brief pinch, but it’s usually over quickly.

What Does the Result Mean?

Results are compared to standard ranges, but your exact values will depend on your health and lab’s guidelines. High or low readings may trigger further testing or adjustments to your treatment plan.

Common Reasons for Abnormal Results

Elevated glucose levels may suggest diabetes, stress, or poor diet, while low levels could indicate insulin issues, certain medications, or severe illness. Your provider will discuss findings with you.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Glucose testing is critical for diagnosing and managing conditions like diabetes, where blood sugar must be carefully balanced. It also helps detect early signs of metabolic disorders or complications from other diseases.

Short name

Serum/Plasma Glucose

Frequently asked questions

Will I Need to Prepare for This Test?
No special preparation is usually needed, but you may be asked to fast (not eat) for 8–12 hours before the test if it’s part of a fasting blood sugar panel.
How Long Will Results Take?
Results are typically available within 1–3 business days, depending on your lab’s processing time. Your provider will contact you once they’re ready.
Can I Eat or Drink Before the Test?
If fasting is required, avoid food and liquids (except water) for the specified period. If not fasting, eat normally, but check with your provider to confirm.
  1. 1
    MedlinePlus — Laboratory TestsSource
  2. 2
    Lab Tests OnlineSource
  3. 3
    Mayo Clinic — Tests & ProceduresSource

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.

Medical Disclaimer

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