Title: WBC count Information | Mount Sinai - New York
Headings: WBC count
WBC count
How the Test is Performed
How to Prepare for the Test
How the Test will Feel
Why the Test is Performed
Normal Results
What Abnormal Results Mean
Risks
References

Content: A lower than normal WBC count may be due to: Bone marrow deficiency or failure (for example, due to infection, tumor, or abnormal scarring)
Cancer treating drugs, or other medicines (see list below)
Certain autoimmune disorders such as lupus ( SLE)
Disease of the liver or spleen
Radiation treatment for cancer
Certain viral illnesses, such as mononucleosis (mono)
Cancers that damage the bone marrow
Very severe bacterial infections
Severe emotional or physical stress (such as from an injury or surgery)
HIGH WBC COUNT
A higher than normal WBC count is called leukocytosis. It may be due to: Certain drugs or medicines (see list below)
Cigarette smoking
After spleen removal surgery
Infections, most often those caused by bacteria
Inflammatory disease (such as rheumatoid arthritis or allergy)
Leukemia or Hodgkin disease
Tissue damage (for example, burns)
There may also be less common reasons for abnormal WBC counts. Drugs that may lower your WBC count include: Antibiotics
Anticonvulsants
Antithyroid drugs
Arsenicals
Captopril
Chemotherapy drugs
Chlorpromazine
Clozapine
Diuretics (water pills)
Histamine-2 blockers
Sulfonamides
Quinidine
Terbinafine
Ticlopidine
Drugs that may increase WBC counts include: Beta adrenergic agonists (for example, albuterol)
Corticosteroids
Epinephrine
Granulocyte colony stimulating factor
Heparin
Lithium
Risks
There is little risk involved with having your blood taken. Veins and arteries vary in size from one person to another, and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others. Other risks associated with having blood drawn are slight, but may include: