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Cancer-related fatigue 101

Fatigue, or the feeling of being tired is the most common symptom people with cancer will have. You can feel fatigued before and during cancer treatment. For some, even after having finished their treatment for cancer, they can feel fatigued for many months or years. Many people with cancer say they didn’t expect the fatigue to have such an impact on their life.  For many people with cancer, it is the symptom that gives them the most trouble.

What causes fatigue?

There are many causes of cancer-related fatigue and often a person will have more than one reason for being fatigued at any given time. There are treatments and things you can do to help with fatigue.  Talk to your health care team  about some of the causes of fatigue.

  • It is important to remember that your body is fighting against your cancer.  This is very hard work and can result in the feeling of fatigue.
  • Cancer treatments can cause fatigue. It is very common for a person who is getting chemotherapy or having radiation treatments to feel fatigued.
  • Another common and treatable cause of cancer-related fatigue is anemia.  When a person is anemic, it means they have fewer red blood cells in their bloodstream than what they would normally have.  Anemia can be caused by cancer itself or can be a side effect of treatments. Sometimes anemia can be treated with medications that increase the body’s production of red blood cells. If you have anemia, your health care team might suggest that you receive a blood transfusion.
  • When a person has been told they have cancer or is having treatment for their cancer, it is very common for this to be an emotional or distressing experience.  This can make a person feel fatigued.
  • It is very common for a person with cancer to have trouble with sleeping.  Waking up often during the night and not getting enough sleep can make fatigue worse.
  • Other symptoms like pain, trouble breathing and nausea (feeling sick to your stomach) can result in fatigue.

What’s important for me to know about fatigue?

Just like pain or nausea (feeling sick to your stomach), fatigue is a real symptom and it can have a big impact on your life.  You might think you are expected to feel fatigue when you have cancer.  You might also think it is not something you need to tell your health care team about. . There are things that can help you feel less tired and it is important for you to talk to your health care team about your fatigue as different suggestions can be made depending on the underlying cause.

Sometimes a person is worried their fatigue might mean their cancer treatment is not working. If you are worried about this, please discuss this with your health care team.

It is important for you to know what you can do about cancer-related fatigue:

  • Exercise regularly (this is the most effective thing you can do to improve your fatigue)
  • Keep a journal or diary of how you feel each day. This can help plan daily activities
  • Let others help with tasks that need to get done (for example laundry or cleaning)
  • Save your energy for the things you enjoy doing
  • Don’t be afraid to ask for help. Friends and family might be willing to help, but may not know what to do.
  • Try to balance activities with rest.
  • Take one short nap not longer than one hour during the day.  If you find you need to sleep more than this please speak to your health care team as this may mean that there are issues other than fatigue that need to be looked at and explored further.

When should I speak to someone about the fatigue I’m feeling? When should I be concerned?

One way to think about whether you should speak to someone about the fatigue you are feeling is to think about how it is affecting your life.  If you are worried or distressed about the fatigue you are experiencing, speak to your health care team.  Also, you can ask yourself these three questions:

  1. Am I more tired in general than before I had cancer?
  2. Am I too tired to do things like go grocery shopping or go out for dinner with friends?
  3. Am I too tired to get out of bed in the morning or get dressed?

If your answer is “Yes” to the first two questions, be sure to discuss fatigue with your health care team during your next visit.  If you also answer, “Yes” to the third question, you or someone you know should contact your health care team right away.  It is concerning if your fatigue is bad enough that it impacts your ability to do things like get out of bed or get dressed.

Fatigue is very common for a person living with cancer.  Many of the underlying causes of fatigue have treatments and ones that you can do yourself without the use of medication however just to be sure that you are following the right path and that there is no other reason for your fatigue it is important to to tell those caring for you at the place you are getting treatment so they can determine what the cause is and to jointly develop a plan to help you.

About the author

Dr. Jeff Myers

Dr. Jeff Myers

Dr. Jeff Myers is head of the Palliative Care Consult Team at Sunnybrook.

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