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Total Serum IgE (Immunoglobulin E) Level

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

This test measures the amount of Immunoglobulin E (IgE), a protein in your blood that plays a key role in allergic reactions.

Quick summary

["IgE levels help identify allergies or immune responses."]

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

Key facts at a glance

LOINC
61299-4
Short code
East White Pine IgE/IgE total %
Synonyms
East White Pine IgE/IgE total %
Category
chemistry
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 Does IgE Measure?

IgE (Immunoglobulin E) is an antibody produced by your immune system in response to allergens like pollen, dust, or certain foods. High levels may suggest allergies, asthma, or other allergic conditions. This test helps doctors diagnose and monitor these conditions.

Why Might You Need This Test?

Your healthcare provider may order this test if you have symptoms like sneezing, itching, rashes, or breathing difficulties that suggest allergies. It can also be used to check for conditions like hay fever, eczema, or certain types of asthma.

How Is the Test Performed?

A small blood sample is taken from a vein in your arm. The blood is then sent to a lab where it is analyzed to measure the IgE levels.

What Are Common Results?

Results are typically reported in International Units per milliliter (IU/mL). Interpretation depends on your symptoms and overall health, as well as any known allergies or conditions.

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.

IgE levels can be elevated in people with allergies, certain types of asthma, or parasitic infections. Low levels may indicate a weakened immune response to allergens. This test is not diagnostic for all conditions but helps guide further evaluation.

Short name

IgE Total

Frequently asked questions

What causes elevated IgE levels?
Elevated IgE levels are often linked to allergic reactions, such as to environmental allergens (e.g., pollen, pet dander), certain foods, or medications. They can also be associated with conditions like asthma, eczema, or parasitic infections.
How long does it take to get results?
Results from this test are usually available within a few days to a week, depending on your lab’s processing times and any follow-up steps required by your healthcare provider.
Can IgE levels change over time?
Yes, IgE levels can fluctuate based on exposure to allergens, underlying health conditions, and treatment. Regular monitoring may be needed if you have a chronic condition like allergies or asthma.
  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