Effects of a Low White Blood Cell Count During Chemotherapy

Health Tip Sheet

Effects of a Low White Blood Cell Count During Chemotherapy

White Blood Cells Protect You

Watch this video of how white blood cells protect against infection by attacking germs that enter your body.


Chemotherapy and White Blood Cells

Woman receiving chemotherapy from a nurseChemotherapy is a commonly used treatment for cancer. These powerful cancer-fighting drugs work by killing the fastest-growing cells in the body—both good and bad. This means that along with killing cancer cells, your healthy white blood cells, called neutrophils, are killed too.

When the number of neutrophils is reduced, a condition called neutropenia occurs and your risk for getting an infection is increased. Between 7-12 days after you finish each chemotherapy dose—and possibly lasting for 5-7 days, your white blood cells are at their lowest numbers. This period of time is often called your nadir, meaning “lowest point”. This is when you are more likely to develop neutropenia. This period varies slightly depending upon the chemotherapy drug, or combination of drugs, used. Your doctor and/or nurse will let you know exactly when your white blood cell count is likely to be at its lowest.

You should watch very carefully for signs and symptoms of infection during this time. During these high-risk days, you should take your temperature any time you feel warm, flushed, chilled, or not well.

Learn more about nadir

How Chemotherapy Affects Your White Blood Cells

Watch this video that shows what happens when the number of white blood cells is reduced (a condition called neutropenia).

If You Have a Low White Blood Cell Count (High Risk)

If chemotherapy is likely to make your white blood cell count very low, you may get medicine to raise your white blood cell count and help lower your risk of infection.
If you have a low white blood cell count, remember that you have a great resource in your doctor or nurse! Be sure to talk to them about ways that you can better cope with low white blood cell counts. They can give you resources and guidance to keep your body as healthy as possible during this time. If you have questions, call your doctor or nurse. They are there to help you.

Remember that when your white blood cell count is low, your body isn’t as well equipped to fight off germs. For this reason, it is very important to reduce your risk of infection and familiarize yourself with the signs and symptoms of infection.


Education Materials

CDC created a variety of resources for patients, caregivers and healthcare providers, including fact sheets and posters.

"I never thought seriously about the risk of infection until I was hospitalized and unable to fight a fever. It’s so important to understand what steps you can take to help protect yourself."Donna Deegan, News AnchorBreast Cancer Survivor 

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