Sesame-Specific IgG, Qualitative — Radioallergosorbent Test (RAST)
A qualitative blood test that looks for antibodies against sesame using RAST methodology. A positive result does not by itself prove a sesame allergy.
["This test can show prior exposure to sesame, but it cannot confirm or rule out an allergy on its own."]
Key facts at a glance
- LOINC
- 21519-4
- Short code
- Deprecated Sesame Seed IgG RAST Ql
- Synonyms
- Deprecated Sesame Seed 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 blood test looks for sesame-specific IgG antibodies using radioallergosorbent test (RAST) methodology. The qualitative result is reported as positive or negative rather than as a measured concentration.
Why might I need this test?
It may be ordered to evaluate a possible reaction to sesame or to help assess previous exposure. Because IgG antibodies are common after exposure, this result usually requires interpretation alongside symptoms, medical history, and other allergy testing.
How is the test performed?
A blood sample is analyzed in a laboratory using sesame allergen and RAST methodology. The laboratory determines whether sesame-specific IgG is detectable and reports a qualitative result.
How do I prepare for the test?
Fasting is generally not required, but follow any instructions provided by the ordering clinician. Tell the clinician about past reactions to sesame, other food allergies, and any allergy treatments or immunotherapy you are receiving.
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 sesame-specific IgG antibodies are present, which may reflect previous exposure rather than a clinically important allergy. A negative result does not completely exclude sesame allergy, especially if symptoms are intermittent or occurred recently. RAST is more commonly used for allergen-specific IgE testing, so confirm the analyte listed on the report with your clinician.
Short name
Sesame IgG (RAST), Qualitative
Frequently asked questions
Does a positive sesame IgG result mean I am allergic to sesame?
Can this test rule out a sesame allergy?
Is this the same as a sesame-specific IgE 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 17, 2026. · Read our editorial policy