Eosinophil Count (Blood)
This test measures the number of eosinophils, a type of white blood cell that helps fight certain infections and responds to allergies.
["Eosinophils help your body defend against parasites and allergens, and their levels can signal underlying health concerns."]
Key facts at a glance
- LOINC
- 32173-7
- Short code
- Eosinophil Bld Ql Wright Stn
- Synonyms
- Eosinophil Bld Ql Wright Stn
- Category
- chemistry
- Sample
- whole-blood
- Container
- Lavender-top (EDTA)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- wright-stain
- Specimen volume
- 3 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h
- Hemolysis max
- 0
- Lipemia max
- 0
- Icterus max
- 0
- TAT
- 4–24 hours
- Order
- routine
What Is an Eosinophil?
Eosinophils are a type of white blood cell that plays a role in defending against parasites, managing allergic reactions, and reducing inflammation. They are part of your immune system and can increase in response to infections, allergies, or certain medical conditions.
Why Might Your Doctor Order This Test?
Your doctor may order an eosinophil count to investigate symptoms like persistent coughing, skin rashes, digestive issues, or unexplained fatigue. It can also help diagnose conditions such as asthma, allergies, parasitic infections, or certain autoimmune diseases.
Common Reasons for Abnormal Results
High eosinophil levels may suggest allergic reactions, parasitic infections, certain lung diseases (like asthma or eosinophilic granulomatosis), or other immune-related conditions. Low levels might indicate stress, certain infections, or immune system suppression, though this is less common.
How Is This Test Performed?
A blood sample is taken from a vein, usually in your arm. The sample is then analyzed in a lab to count the number of eosinophils among your white blood cells.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
◆Associated findings1
Short name
Eosinophil Blood Test
Frequently asked questions
What does a high eosinophil count mean?
A low eosinophil count is less common but may occur with chronic stress, certain infections, or immune system suppression. Your doctor will review your overall health and test results to identify potential causes.
Can lifestyle changes affect eosinophil levels?
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