Blood and lab tests
What Is WBC on a Blood Test? White Cell Count Explained
WBC (White Blood Cell Count) · say it: dub-ul-you-bee-SEEAlso written: white blood cell count, white cell count, WCC, leukocyte count
Short answer
WBC is the number of white blood cells in a sample of your blood; these cells are part of the immune system that fights infection.
What it means
White blood cells (leukocytes) defend the body against germs and help with healing. There are several kinds, including neutrophils, lymphocytes, monocytes, eosinophils and basophils.
The WBC count is the total of all types. A higher count is often a response to infection, inflammation, stress, smoking or some medicines such as steroids. A lower count can follow some viral infections, medicines or conditions affecting the bone marrow.
A "differential" breaks the total down into each type of white cell. Doctors usually look at the differential, not just the total, to understand what is happening.
Where you may see it
- Complete blood count (CBC)
- Infection and inflammation assessments
- Monitoring during treatments that affect the bone marrow
📄 How it looks on a report
WBC 11.8 x10^9/L H
🙅 What it does not mean
- A high WBC does not always mean infection; stress, exercise, pregnancy, smoking and steroids can raise it.
- It does not by itself point to any specific illness.
- A slightly low WBC can be normal for some healthy people and some ethnic backgrounds.
🗒️ Questions to ask your doctor
🧾 Reports where you will see “WBC (White Blood Cell Count)”
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💊 Medicines whose labels mention “WBC (White Blood Cell Count)”
Plain-English explanations of each medicine, from its official FDA label.
- Aripiprazole
an atypical antipsychotic medicine
- Methotrexate
A dihydrofolate reductase inhibitor, a type of medicine that works against folate (a vitamin-like substance cells use to grow and divide). The FDA pharmacologic class is not listed on the label.
- Mirtazapine
An antidepressant medicine. The label describes it as having a tetracyclic chemical structure and belonging to the piperazino-azepine group of compounds.
- Quetiapine
An atypical antipsychotic medicine
- Risperidone
an atypical antipsychotic medicine
- Spironolactone
An aldosterone antagonist, a type of prescription medicine the FDA classifies this way
🔗 Read more from trusted sources
- “WBC (White Blood Cell Count)” on MedlinePlus ↗
US National Library of Medicine
- NCI Dictionary definition ↗
US National Cancer Institute: “wbc”
- MedlinePlus lab test guides ↗
US National Library of Medicine
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General information about a medical word, not advice about your own results. Ask the clinician who ordered the test what it means for you.