Regional Allergen Mix 4-Specific IgE (RAST), Serum
A blood test that measures IgE antibodies to a group of environmental allergens commonly encountered in a particular region.
["Elevated allergen-specific IgE may indicate an allergy to one or more allergens included in the panel."]
Key facts at a glance
- LOINC
- 82108-2
- Short code
- Region Allerg Mix4 IgE RAST
- Synonyms
- Region Allerg Mix4 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 allergen-specific IgE antibodies in your blood. It is sometimes called a RAST test and evaluates your immune response to a regional group of environmental allergens.
Why might I need this test?
Your clinician may order it to help identify possible triggers of allergy symptoms such as sneezing, congestion, wheezing, or itchy eyes. The results may guide allergy testing, avoidance, or treatment decisions.
How is the test performed?
A blood sample is drawn and analyzed for IgE antibodies to the allergens in the regional mix. The laboratory may report results for individual allergens or for the allergens as a group, depending on the panel used.
How do I prepare for the test?
No special preparation is usually needed. Tell your clinician about current antihistamine or other allergy medicines, because some treatments can affect test results.
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.
An elevated result suggests that your immune system has produced IgE antibodies to the tested allergen, but it does not by itself prove that the allergen causes your symptoms. Results should be interpreted with your exposure history, symptoms, and other allergy tests by your clinician.
Short name
Regional Allergen Mix 4 IgE
Frequently asked questions
Does this test diagnose an allergy?
What allergens are included in Regional Allergen Mix 4?
Should I stop taking allergy medicine before the 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