Total Immunoglobulin E (IgE) Level
This test measures the amount of Immunoglobulin E (IgE), a type of antibody in your blood that can react to allergens. IgE levels may help identify allergies or other immune-related conditions.
["IgE tests help diagnose allergies or immune system disorders by checking for elevated antibody levels."]
Key facts at a glance
- LOINC
- 48402-2
- Short code
- Ltx IgE/IgE total %
- Synonyms
- Ltx IgE/IgE total %
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- 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 This Test Measure?
IgE is a protein produced by your immune system in response to allergens like pollen, dust mites, or certain foods. While IgE is normally present in small amounts, higher levels may indicate an allergic reaction or an overactive immune response.
Why Might You Need This Test?
Your doctor may order this test if you have symptoms like sneezing, itching, rash, or breathing difficulties that suggest allergies. It can also be used to monitor conditions like asthma, eczema, or chronic urticaria (hives).
How Is the Test Performed?
A blood sample is taken from a vein in your arm. The sample is then sent to a lab for analysis using an immunoassay method to measure IgE levels.
What Are Common Results?
Results are typically reported as a numerical value representing the concentration of IgE in the blood. While specific reference ranges vary by lab, elevated IgE levels may suggest allergies or immune disorders.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
High IgE levels often point to allergies, where the immune system reacts excessively to harmless substances. It may also be linked to conditions like hay fever, food allergies, or certain autoimmune diseases. Low IgE levels are less commonly significant but may sometimes indicate a weakened immune response or specific immune deficiencies.
Short name
IgE Total
Frequently asked questions
What causes elevated IgE levels?
A normal IgE level doesn’t rule out allergies entirely, as some people may have mild reactions or allergies without elevated IgE. Your doctor may recommend further testing or monitoring if symptoms persist.
The blood draw for this test is generally mild discomfort, similar to a standard blood test. Most people feel little to no pain afterward, though some may experience slight bruising or swelling at the injection site.
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 16, 2026. · Read our editorial policy