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Anemia: Cancer Treatment Side Effect

Doctor reassuring her patient who looks very tired.

Tell your doctor if you are extremely tired or have other signs of anemia. There are treatments that may help.

Credit: iStock

What is anemia?

Anemia is a condition in which the number of red blood cells is below normal. 

What are signs of anemia?

Anemia can make you feel very tired, short of breath, and lightheaded. Signs of anemia may also include feeling dizzy or faint, headaches, a fast heartbeat, and/or pale skin.

What causes anemia in people with cancer?

Cancer treatments, such as chemotherapy and radiation therapy, as well as cancers that affect the bone marrow, can cause anemia. When you are anemic, your body does not have enough red blood cells. Red blood cells are the cells that that carry oxygen from the lungs throughout your body to help it work properly.

You will have blood tests to check for anemia. Treatment for anemia is also based on your symptoms and on what is causing the anemia.

Ways to manage anemia

Here are some steps you can take if you have fatigue caused by anemia:

  • Save your energy and ask for help. Choose the most important things to do each day. When people offer to help, let them do so. They can take you to the doctor, make meals, or do other things you are too tired to do.
  • Balance rest with activity. Take short naps during the day, but keep in mind that too much bed rest can make you feel weak. You may feel better if you take short walks or exercise a little every day.
  • Eat and drink well. Talk with your doctor, nurse, or a registered dietitian to learn what foods and drinks are best for you. You may need to eat foods that are high in protein or iron.

Questions to ask your health care team about anemia

Prepare for your visit by making a list of questions to ask. Consider adding these questions to your list:

  • What is causing the anemia?
  • What problems should I call you about?
  • What steps can I take to feel better?
  • Would medicine, iron pills, a blood transfusion, or other treatments help me?
  • Would you give me the name of a registered dietitian who could also give me advice?


Listen to tips on how to manage fatigue from cancer treatments such as radiation therapy.
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