Glucose measured in gastric fluid (fasting, 2-hour post-meal)
This test checks the level of glucose (sugar) in your stomach fluid after eating or fasting. It helps assess how your body handles glucose, which is important for diagnosing conditions like diabetes or digestive issues.
["This test helps doctors understand how your digestive system and metabolism work together to manage blood sugar levels."]
Key facts at a glance
- LOINC
- 14386-7
- Short code
- Glucose Gast-mCnc
- Synonyms
- Glucose Gast-mCnc
- Category
- glucose
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- 50 N/A – 400 N/A
- Fasting
- true
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- CPT
- 84484
- SNOMED
- 302774002
- 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 doctor may order this test if they suspect digestive problems that affect how food is broken down or absorbed, or if they want to evaluate how your body responds to glucose after eating. It can also be part of diagnosing conditions like celiac disease, diabetes, or other metabolic disorders.
What to Expect Before the Test
You’ll likely fast for 12 hours before the test, meaning no food or drink (except water) for that period. If you’re having the 2-hour post-meal test, you’ll eat a small meal or drink a glucose solution before the sample is taken. Follow your doctor’s specific instructions carefully.
What Happens During the Test?
A healthcare provider will collect a small sample of fluid from your stomach using a tube inserted through your nose into your stomach. The sample is then sent to a lab for analysis. The process is usually quick and doesn’t cause much discomfort.
What the Results Mean
The results show the amount of glucose in your stomach fluid at specific times. High or low levels can indicate problems with digestion, absorption, or metabolism. Your doctor will compare these results to your overall health and symptoms to make a diagnosis.
Reference range
Adult: 10-40 U/LN/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.
◆Associated findings1
Short name
Gastric Fluid Glucose Test
Frequently asked questions
How often will I need to take this test?
What do my test results mean if they’re outside of normal ranges?
Can I eat or drink anything 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