🩸 Hematology

Eosinophil: What It Means for Your Health

Eosinophils are specialized white blood cells that fight parasitic infections and play a central role in allergic and inflammatory reactions. They release toxic granules that kill parasites but can also damage host tissues in allergic conditions like asthma and eczema. Eosinophils typically make up 1-4% of white blood cells.

Full Name
Eosinophil Percentage
Normal Range
1–4 %
Also Known As
Eosinophil %, EOS, Eos

Reference Range

LowNormal: 1–4 %High

Reference ranges may vary between laboratories, age groups, and sexes. The values shown are general adult reference ranges. Always compare your results to the specific range provided by your testing laboratory.

What Is Eosinophil?

Eosinophils are specialized white blood cells that fight parasitic infections and play a central role in allergic and inflammatory reactions. They release toxic granules that kill parasites but can also damage host tissues in allergic conditions like asthma and eczema. Eosinophils typically make up 1-4% of white blood cells.

Commonly included in:

Complete Blood Count (CBC)WBC Differential

What Does High Eosinophil Mean?

Above 4 %

Elevated eosinophils (eosinophilia) commonly indicate allergic conditions (asthma, hay fever, eczema, drug allergies), parasitic infections, autoimmune diseases, eosinophilic esophagitis, or rarely, hypereosinophilic syndrome or certain cancers (Hodgkin lymphoma).

What Does Low Eosinophil Mean?

Below 1 %

Low eosinophil count is usually not clinically significant. It can occur with acute stress, Cushing syndrome, or corticosteroid use, as cortisol naturally suppresses eosinophil production.

Related Biomarkers in Hematology

Hemoglobin
Oxygen-carrying protein found inside red blood cells.
Range: 12–17.5 g/dL
Hematocrit
Percentage of blood volume occupied by red blood cells.
Range: 36–50 %
WBC
Total white blood cell count measuring immune system activity.
Range: 4.5–11 10^3/uL
RBC
Total number of red blood cells in your blood.
Range: 4–5.5 10^6/uL
Platelet
Blood cells responsible for clotting and wound healing.
Range: 150–400 10^3/uL
MCV
Average size of your red blood cells.
Range: 80–100 fL

Track Your Eosinophil Over Time

Upload your blood test results to Hemoly and see how your Eosinophil levels change over time. Get trend analysis, educational insights, and a personal health timeline.

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Medical Disclaimer

This information is for educational purposes only and is not intended as medical advice, diagnosis, or treatment. Reference ranges may vary between laboratories. Always consult a qualified healthcare professional for interpretation of your blood test results and before making any health decisions.