Interleukin-5 (IL-5) concentration in serum or plasma
This test measures the amount of interleukin-5, a protein involved in regulating immune responses, particularly in the production of certain white blood cells.
["IL-5 helps your immune system respond to allergies and chronic inflammatory conditions."]
Key facts at a glance
- LOINC
- 44321-8
- Short code
- Il5 SerPl Ql
- Synonyms
- Il5 SerPl Ql
- 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 Is Interleukin-5 Used For?
IL-5 is primarily studied in research contexts, including evaluating immune responses in conditions like asthma, allergic reactions, and certain autoimmune diseases. It may also be monitored in clinical trials for treatments targeting chronic inflammation or immune disorders.
How Is This Test Performed?
A blood sample is drawn from a vein, typically in your arm. The sample is then processed to separate serum or plasma, where IL-5 levels are measured using an immunoassay method to detect and quantify the protein.
What Does a High or Low IL-5 Level Mean?
Elevated IL-5 levels may suggest an overactive immune response, such as in severe allergies, asthma, or certain inflammatory conditions. Lower levels might indicate reduced immune activity, though this is less common in routine testing.
Common Conditions Monitored
IL-5 is not routinely tested for general health but may be assessed in specialized cases, such as research studies, allergy testing, or monitoring immune-related treatments for chronic conditions.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Clinical Significance: IL-5 plays a key role in the differentiation of eosinophils (a type of white blood cell) and is linked to allergic inflammation. Elevated IL-5 is often associated with conditions like allergic asthma, atopic dermatitis, or eosinophilic disorders. However, its clinical use in diagnosis or treatment is limited to research or targeted therapies.
Short name
IL-5 Level
Frequently asked questions
Why might my doctor order this test?
What should I expect during or after the test?
Are there any risks or side effects?
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