Flounder-Specific IgG, Radioallergosorbent Test (RAST), Qualitative (Deprecated)
A qualitative blood test that looks for IgG antibodies to flounder. A positive result shows immune exposure but does not by itself diagnose a flounder allergy.
["A positive result means flounder-specific IgG was detected, but it does not confirm an allergy."]
Key facts at a glance
- LOINC
- 21274-6
- Short code
- Deprecated Flounder IgG RAST Ql
- Synonyms
- Deprecated Flounder IgG RAST Ql
- Category
- liver
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Ref low
- 10
- Ref high
- 40
- Critical range
- — – 500 N/A
- Fasting
- false
- 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
What is this test?
This is a qualitative test for flounder-specific immunoglobulin G (IgG) antibodies in blood. It is a legacy test that is no longer generally available, and the RAST label is unusual because RAST is more commonly used for IgE testing.
Why might I need this test?
It may have been ordered to evaluate immune exposure to flounder or to help investigate a suspected food-related reaction. Food-specific IgG results are generally supportive information rather than a stand-alone diagnosis of allergy.
How is the test performed?
A blood sample is analyzed in a laboratory for antibodies that bind flounder proteins. Because the result is qualitative, it is generally reported as detectable or not detected rather than as a specific concentration.
How do I prepare for the test?
No special preparation is usually required for this blood test unless your healthcare provider gives different instructions. Tell the provider about any fish reactions, recent flounder exposure, allergy treatments, and other allergy testing you have had.
Reference range
Adult: 10-40 U/LN/A
No special preparation required. Avoid fatty meals before the test if possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
A positive result indicates that flounder-specific IgG antibodies were detected, which may reflect prior exposure or immune sensitization. IgG antibodies can occur in people without symptoms and do not by themselves establish an immediate flounder allergy. Results should be interpreted with symptoms, exposure history, and other allergy testing when appropriate.
Short name
Flounder-specific IgG test
Frequently asked questions
Does a positive result mean I am allergic to flounder?
What tests may be more useful for suspected fish allergy?
Why is this test labeled deprecated?
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