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Eosinophil Count (Peripheral Blood, Manual Qualitative Evaluation)

Published: August 9, 2026Updated: August 16, 2026

This test checks the number of eosinophils, a type of white blood cell, in your blood. Eosinophils help fight certain infections and respond to allergies or inflammation.

Quick summary

["Eosinophils may rise when you have allergies, infections, or other immune responses."]

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
33803-8
Short code
Imm Eosinophil NFr Bld Manual
Synonyms
Imm Eosinophil NFr Bld Manual
Category
chemistry
Sample
whole-blood
Container
Lavender-top (EDTA)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
manual-count
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

Why This Test Might Be Ordered

Your healthcare provider may recommend this test if you have symptoms like persistent itching, skin rashes, asthma, or unexplained allergic reactions. It could also be used to monitor conditions like parasitic infections, certain cancers, or chronic inflammatory diseases.

What to Expect Before the Test

No special preparation is needed. You’ll have a small needle inserted into your arm to draw blood. This is usually done in a lab setting and takes a few minutes.

What the Test Results Mean

Results are qualitative (yes/no or high/low) rather than a specific number. High eosinophil levels may suggest allergies, infections, or other immune-related conditions. Low levels might indicate certain infections or immune disorders.

Common Conditions Linked to Eosinophil Levels

Elevated eosinophils are often seen in allergic reactions, parasitic infections, asthma, or certain autoimmune diseases. Low eosinophils may be linked to viral infections or conditions affecting white blood cell production.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

Clinical significance: Eosinophil counts are critical for diagnosing and managing conditions like allergic disorders, parasitic infections, and certain cancers. They help guide treatment decisions by indicating the body’s immune response.

Short name

Eosinophil count (qualitative)

Frequently asked questions

What causes eosinophil levels to change?
Eosinophil levels can rise due to allergies, infections (like parasites), asthma, or inflammatory diseases. They may drop due to viral infections, certain medications, or conditions affecting blood cell production.
How long does it take to get results?
Results are typically available within 1–2 business days, depending on lab processing times. Your provider will discuss them with you during your follow-up visit.
Can I eat or drink before this test?
No special diet is required. You can eat and drink normally, but avoid heavy meals just before the blood draw if your provider advises it.
  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 16, 2026. · Read our editorial policy