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Food Allergen Mix 2 IgE, Serum — Radioallergosorbent Test (RAST)

Published: August 9, 2026Updated: August 17, 2026

A blood-based allergy test that measures IgE antibodies to a defined group of foods, helping assess possible food allergy along with your medical history.

Quick summary

["Detectable IgE to a food allergen may indicate sensitization, but it does not by itself confirm a clinical food allergy."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 17, 2026Editorial policy

Key facts at a glance

LOINC
24487-1
Short code
Food Allerg Mix2 IgE RAST
Synonyms
Food Allerg Mix2 IgE RAST
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
Method
multidisk
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 test measures food allergen-specific IgE antibodies in blood using a laboratory-defined mixture of food allergens. The exact foods included can vary, so the laboratory's test directory or result report should identify the individual allergens tested.

Why might I need this test?

It may be used to evaluate suspected food allergy, especially when symptoms occur after eating a particular food. Results are most useful when considered with your symptoms, exposure history, examination, and other allergy testing.

How is the test performed?

A blood sample is collected, and the laboratory measures IgE antibodies against the allergens in the mixture. The RAST label refers to the radioallergosorbent testing method; laboratories may use other validated IgE immunoassays.

How do I prepare for the test?

No fasting is usually required. Tell your clinician about all medicines and supplements you use, and do not stop prescribed antihistamines or other medicines without medical advice. Continue avoiding any food that has caused a serious reaction unless your clinician instructs otherwise.

Reference range

Adult: 10-40 U/LN/A

Specimen: serum

No special preparation required. Avoid fatty meals before the test if possible.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

◆Associated findings1

Short name

Food Allergen Mix 2 IgE

Frequently asked questions

Does a positive result mean I have a food allergy?
Not necessarily. It indicates that IgE antibodies to a tested food were detected, which can reflect sensitization rather than a symptomatic allergy. Your medical history and other test findings are needed to make a diagnosis.
What foods are included in Food Allergen Mix 2?
The mixture is laboratory-defined and may not be the same at every testing laboratory. Check the test order or result report for the individual allergens included.
Do I need to stop taking allergy medicines before the test?
Do not stop medicines on your own. Antihistamines and some other treatments may affect interpretation, so ask your clinician whether any medication changes are necessary.
  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 17, 2026. · Read our editorial policy