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Cancer-Related Fatigue

Fatigue is feeling tired - physically, mentally, and emotionally

image of person napping

According to the American Cancer Society, cancer-related fatigue is the most common side effect of cancer and cancer treatment. Fatigue is feeling tired - physically, mentally, and emotionally. It means having less energy to do the things you normally do or want to do. In people with cancer, it can be caused by the cancer itself, cancer treatment, and other factors.

The fatigue that comes with cancer is different from the fatigue of daily life. Every day, normal fatigue is most often a short-term problem that gets better with rest. Cancer-related fatigue is worse and it causes more distress. Rest does not make it go away, and just a little activity may make you feel exhausted.

Research suggests that anywhere between 70% and 100% of cancer patients getting treatment have fatigue. And about 30% to 50% of cancer survivors have said that their fatigue lasts for months or even years after they finish treatment.

What Causes Fatigue in People with Cancer?

Fatigue in cancer patients may have more than one cause.

Doctors do not know all the reasons cancer patients have fatigue. Many conditions may cause fatigue at the same time.

Fatigue in cancer patients may be caused by the following:

  • Cancer treatment with chemotherapy, radiation therapy, and some biologic therapies.
  • Anemia (a lower than normal number of red blood cells).
  • Hormone levels may be too low or too high.
  • Trouble breathing or getting enough oxygen.
  • Heart trouble.
  • Infection.
  • Pain.
  • Stress.
  • Loss of appetite or not getting enough calories and nutrients.
  • Changes in how well the body uses food for energy.
  • Loss of weight, muscle, and/or strength.
  • Medicines that cause drowsiness.
  • Problems getting enough sleep.
  • Being less active.
  • Other medical conditions.

Fatigue is common in people with advanced cancer who are not receiving cancer treatment.

How cancer treatments cause fatigue is not known

Doctors are trying to better understand how cancer treatments such as surgery, chemotherapy, and radiation therapy cause fatigue.

Different cancer treatments have different effects on a patient's energy level. The type and schedule of treatments can affect the amount of fatigue caused by cancer therapy. Some treatments that may cause fatigue:

  • Chemotherapy
  • Radiation Therapy
  • Biologic Therapy
  • Surgery


Here is a list of some signs of fatigue that you and your family can watch for. Talk to your doctor if you have any of them.

  • You feel tired and it does not get better, it keeps coming back, or it becomes severe.
  • You are more tired than usual during or after an activity.
  • You are feeling tired and it is not related to an activity.
  • Your tiredness does not get better with rest or sleep.
  • You sleep more.
  • You become confused.
  • You can't concentrate or focus your thoughts.
  • You have no energy.
  • You are unable to get out of bed for more than 24 hours.
  • Your tiredness disrupts your work, social life, or daily routine.
  • You have no desire to do the things you normally do.
  • You feel negative, sad, or irritable.


Learning about fatigue patterns, how bad it might be, and how long it may last are key parts of dealing with fatigue. It may be helpful to have a family member come to your appointment and help you talk to your health care team about your fatigue.

Tips to manage and reduce your fatigue:

  • List your activities in order of how important they are to you, so you can do the more important ones when you have the most energy.
  • Ask for help and have other people do things for you when possible.
  • Focus on one thing at a time; don't try to multi-task.
  • Put things that you often use within easy reach.
  • Set up and follow a structured daily routine, keeping as normal a level of activity as possible.
  • Balance rest and activity. Too much time in bed can make you weak. Try to avoid it. Schedule activities so that you have time for plenty of rest that does not interfere with nighttime sleep. A few shorter rest periods are better than one long one.
  • Learn ways to deal with your stress. Try to reduce it using things like deep breathing, imagery, meditation, prayer, talking with others, reading, listening to music, painting, or any other things you like to do.
  • Keep a record of how you feel each day. Take it with you when you see your doctor.
  • Talk to your doctor about how to manage any pain, nausea, or depression you may have.
  • Talk to your doctor about physical exercise before you start an exercise program.
  • Get fresh air, if possible.
  • Unless you are given other instructions, eat a balanced diet that includes protein (meat, milk, eggs, and beans) and drink about 8 to 10 glasses of water a day.

The first thing to do for fatigue is talk to your doctor or nurse about it. Let them know how bad it is so you can get the help you need to deal with it.

"Chemobrain" and Fatigue - TIPS

Many cancer patients suffer cognitive deficits, especially memory loss and attention deficits. Chemobrain is probably compounded by stress and fatigue. Bernadine Cimprich, U-M associate professor of nursing, said research has found that exercise, yoga, meditation and spending time in nature have a measurable impact in reducing fatigue. In addition, consider these lifestyle approaches:

  • Focus on the priorities that are most important to you. Delegate tasks or leave other things undone.
  • When you approach a task that requires a lot of mental energy, break it down into smaller goals.
  • Don't try to multitask, especially in situations where it could be dangerous, for example, when driving or while cooking.
  • Schedule your day in advance. Having a structure will help you complete tasks.
  • Rely on family and friends to help you. If you're having trouble making simple decisions -- like meal planning -- ask if they would help with decision-making and shopping.
  • Use a buddy system. For situations where you are concerned that you may be making a mistake, ask someone to look over your work. If you need to read something complex, ask someone to talk it over with you to make sure you fully understand.

University of Michigan Resources