Anemia, a condition where the body has fewer red blood cells than it should, is a common side effect of some breast cancer treatments including radiation, chemotherapy, and some targeted therapies. Red blood cells carry hemoglobin, a protein that allows them to bring oxygen from the lungs to your organs and other parts of the body. Red blood cells usually live for about 120 days but breast cancer and treatments may shorten that lifespan, causing anemia. With fewer red blood cells there to carry oxygen, your body may not function as well as it should.

There are different types of anemia. Some are inherited from your parents, but others can be caused by medicines or a diet that is missing nutrients like iron or vitamin B12.

Many cases of anemia are mild and short-term. You may not even feel any symptoms before being diagnosed by a blood test. In these cases you may not get any medical treatments, though your doctors will watch in case it gets worse. More severe cases of anemia can be treated with medicines, supplements or blood transfusions. Even if your doctors do not recommend a medicine, there are actions you can take to manage anemia or its symptoms.


What does anemia feel like?

If you have anemia, there is not enough oxygen being carried from your lungs to the rest of your body. The most common effect of this is fatigue, a feeling of extreme tiredness and a lack of energy to do the things you need or like to do. If you are feeling tired or weak and it is getting in the way of your daily activities, ask your doctor to test for anemia. Other symptoms of anemia include

  • dizziness
  • shortness of breath
  • headaches
  • pale skin
  • cold hands or feet
  • swelling of hands or feet
  • chest pain

Not everyone will experience every symptom of anemia. You may only feel some of these symptoms, or you might only feel very tired. In very mild cases, you may find out you have anemia after a blood test, but never feel these symptoms at all. Speak with your doctor about any symptoms you have and how to best treat or manage them.

Because there is less oxygen being carried by your blood, your heart may work harder to get oxygen throughout the body. Make sure to tell your doctors about any heart problems you already have because that extra work could make existing heart problems worse.


What causes anemia?

Different types of anemia can be caused by genes you inherited from your parents, a lack of certain vitamins in your diet, cancer or exposure to treatments like radiation and chemotherapy.

Chemotherapy and radiation can affect your bone marrow, where new blood cells are grown. Platinum-based chemotherapy medicines like cisplatin (Platinol) and carboplatin (Paraplatin) are more likely to cause anemia than other chemotherapies. People who had low hemoglobin levels before cancer treatment are also more likely to develop anemia. Other reasons you may experience anemia include blood loss or your body destroying red blood cells too quickly.

Anemia is diagnosed using a test called the complete blood count which measures a number of features of your blood. Most important to diagnosing anemia is the amount of space taken by your red blood cells and the level of hemoglobin in your blood.


How is anemia treated?

Many mild cases of anemia are not treated medically. Your doctors will watch your blood levels to see that it does not get worse and may suggest ways to get more iron and vitamins through food that help red blood cells grow. For more serious cases, there are treatments to help raise the number of red blood cells in your body.

One way to treat anemia is to go after the cause. If the anemia is severe and caused by cancer treatments, your doctor may change the dose or delay treatment to help you get to healthy hemoglobin levels.

Some types of anemia result from not getting enough of certain nutrients, specifically iron or vitamin B12. You may be able to get more of these nutrients by adding certain foods to your diet, but if you are not able to get what your body needs from food your doctor may recommend vitamin supplements. You should always talk with your doctor before deciding to take a vitamin or supplement, because some may interact with your cancer medicines.

There are also medicines that help the body make more red blood cells in more severe cases of anemia. Known as erythropoietic therapy, these medicines act like a hormone that tells your body to make red blood cells. They help raise hemoglobin levels and may mean fewer transfusions for severe cases, but the possible side effects can be serious. Your doctor may recommend an iron supplement along with the medicine. Speak with your doctor about the benefits and the risks of taking these medicines.

Blood transfusions are when you are given blood donated by another person, or blood you had taken and stored before treatment. They are commonly used to replace blood lost because of an injury or condition and to treat severe cases of anemia. A blood transfusion will put red blood cells into your system quickly where medicines may take weeks before having an effect, but the effect of transfusions is temporary. You may still have to be treated for what is causing the anemia, take a medicine to help your body make more blood cells or get more transfusions. Transfusions also come with possible side effects. The most common is your body’s immune system attacking the new cells causing symptoms similar to an allergic reaction. There is a small chance of infections, lung injury, and iron levels that get too high.


How do I manage anemia?

Because many cases of anemia are mild and not treated with medicine, you may find ways to manage symptoms and keep your hemoglobin closer to healthy levels through some lifestyle changes.

The most common symptom of anemia is tiredness. You may not have the energy to do all your daily activities. Saving energy for more important tasks may help you get more done while feeling better than trying to do too much when you are feeling tired. Figure out what needs to be done soon and what can be saved for another day, or ask for help from friends and family.

Make sure you get a full night’s sleep and leave yourself breaks between tasks. It is okay to nap if you feel tired but keep them shorter than an hour and at least 4 hours before your bedtime. Napping too long will actually cause trouble falling asleep at your bedtime.

You can also eat more foods that are high in iron, an important nutrient for making hemoglobin and red blood cells. Iron-rich foods you can add to your diet include

  • dark green, leafy vegetables like spinach
  • many kinds of beans, peas, and lentils
  • meat and fish
  • dried fruits, like apricots, peaches, and prunes
  • bread, cereals, and pastas with added iron

Other nutrients to look for are folic acid and vitamins B12 and C. Like iron, folic acid, and vitamin B12 are added to some cereals, other grains, and soy-based foods. They are found in eggs and beef liver as well. Vitamin C is found in fruits and vegetables, especially citrus fruits like grapefruit and oranges.

Most importantly, speak with your doctors who will try to identify the cause of the anemia. Knowing the reason for the anemia will affect how it is treated or managed. They should be watching your hemoglobin levels to see if they are getting better or worse, but tell them any symptoms you experience. If your hemoglobin levels still drop or you report continuing symptoms, your doctors may recommend supplements or medicines. It is OK to ask why a certain treatment is being recommended and what the possible side effects are. If your anemia was identified as a result of surgery, chemotherapy or radiation therapy, expect it to take about 4 months after the treatment ends for your hemoglobin to return to normal.


Reviewed and updated: January 20, 2017

Reviewed by: Ann Berger, PhD, RN, AOCN, FAAN


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