Fatigue is a common symptom in people with cancer that causes a lack of energy for many usual activities. Most people receiving cancer treatment experience fatigue, and some cancer survivors have fatigue for months and even years after finishing their treatment. Cancer-related fatigue is different than other types of fatigue, like what happens when you don’t get enough sleep, because this feeling of exhaustion does not improve with rest.

Fatigue's effect on quality of life

Fatigue can have negative effects on the overall physical, psychological, social, and economic well-being of people with cancer. For some it can be slightly bothersome, while for others the experience can be devastating. Fatigue can influence a person's:

• Daily activities
• Hobbies and other enjoyable activities
• Social relationships
• Mood and emotions
• Job performance
• Feeling of well-being and sense of joy
• Attitude toward the future
• Ability to undergo treatment

Identifying the causes of fatigue

There are multiple causes of cancer fatigue, but not all of them are well understood. In situations where many different reasons contribute to a sense of exhaustion, it is still important to develop effective strategies to help deal with this symptom. Some of the common causes of fatigue include:

• The cancer itself
• Appetite loss [1]
• Cancer-related treatment
• Anemia [2] (low red blood cell count)
• Uncontrolled pain [3]
• Stress
• Depression
• Lack of sleep
• Medications
• Lack of regular exercise
• Inadequate nutrition
• Co-existing medical conditions [4]

Strategies to help cope with fatigue

Exercising and eating healthy. Researchers now think that a regular exercise program is the best strategy to help relieve cancer-related fatigue. Athletes and physically fit individuals may continue a program of modified regular exercise while undergoing some cancer treatments. However, most people with cancer will experience some degree of deconditioning, making their regular exercise routine more difficult and, in some cases, even dangerous. Exercise helps prevent muscle loss and once lost, resistance training can help to rebuild it. Talk with your doctor about modifying your exercise program to meet your needs. A gradual program will increase muscle tone and lead to a sense of well-being. Even people who are weak benefit from getting out of bed and walking around the house. Read more about physical activity and cancer [5].

Eating well and drinking enough fluids are important to maintaining an adequate weight and meeting your body’s nutritional requirements. Read more about the importance of hydration [6]. If available, consider talking with a nutrition counselor or registered dietitian (RD) at your treatment center. He or she can provide helpful hints on eating a well-balanced diet, as well as tips on eating when there is a lack of taste and during times of nausea and vomiting. Find nutrition recommendations for during and after treatment [7].

Conserving your energy. Many people who complete treatment expect an immediate return to normal functioning. However, fatigue may take some time to resolve, so it is important to prioritize tasks and schedule periods of rest whenever possible. Plan your days so you are able to use the time when you have the most energy for the most important tasks. This includes exercise. Some people may be able to maintain the same lifestyle by scheduling activities when they feel their best. It is important to get the rest you need, which may mean altering the times you sleep and the amount of sleep you need.

Some people also experience mental fatigue, making it difficult to concentrate. It may also contribute to feelings of being overwhelmed and frustrated because your lifestyle has been disrupted. Talk with your doctor, nurse, or social worker about these concerns.

Sharing responsibilities with family and friends. It may be helpful to seek assistance with everyday activities and delegate some of these tasks to others. Maintaining certain household and family responsibilities, such as childcare, meal preparation, and food shopping, may become difficult. Some online communities [8] offer tools to help coordinate caregiving tasks among family members and friends. Health care professionals, such as social workers, will often counsel patients to ask for help from friends and family members. Read about how an oncology social worker can help [9].

Treating fatigue related to anemia. Many patients with cancer have anemia, which is a decrease in the amount of circulating red blood cells. Anemia [2] may be caused by the cancer or cancer-related treatments. Patients who have anemia also report a feeling of extreme and overwhelming fatigue. The treatment for anemia may include nutritional supplements, drugs, and/or blood transfusions.

Managing other causes of fatigue (such as pain, depression, and lack of sleep). Living with constant pain will almost always make a person feel exhausted. Many of the medications usually prescribed for the treatment of pain also cause drowsiness, sleepiness, and fatigue. Your doctor can help you understand the options available and give you information about common side effects of pain medications. Learn more about managing and treating cancer pain [10].

In addition to physical reasons that contribute to fatigue, the situation itself can lead to feelings of distress and depression. This can elevate the feeling of exhaustion and complicate treatment. If a person feels exhausted all the time, he or she may be unable to perform at work or at home. The first step in treating depression is to recognize it as a condition and then talk about ways to resolve it with your doctor. Treatment for depression can make a huge difference and is regularly offered to patients who experience extreme sadness or hopelessness. Learn more about depression [11].

Sleep is necessary for normal function and performance. Stress, pain, and worry can interfere with a person's ability to sleep through the night. In some cases, medications can also disturb normal sleep patterns. For those who are chronically tired, sleep may come in spurts at different times of the day or evening. What is important to remember is that if you are not refreshed by sleep or simply unable to sleep more than one to two hours, it will contribute to feelings of exhaustion and will likely affect your mood and performance. Talk with your doctor and nurse about any sleep problems, and read these strategies for a better night’s sleep [12].

Coping with fatigue in the workplace. Cancer-related fatigue can also affect a person's ability to work. It is common for most people undergoing cancer treatment to make changes to their work schedule and/or responsibilities. Even long-term survivors of cancer who still experience some fatigue may require changes in their work routine. If you are comfortable with your employer knowing about your cancer, talk with a human resources representative about the effects fatigue has had on your ability to maintain your job responsibilities and about any adjustments or accommodations that can be made. You may need to take prolonged sick leave or disability leave in some situations. It is important that you know your company's policy on sick leave and to understand the Americans with Disabilities Act and Family Medical Leave Act so you know your rights. Read more about cancer and the workplace [13] and going back to work after cancer [14].

More Information

Managing Side Effects: Fatigue [15]

ASCO Answers Fact Sheet: Cancer-Related Fatigue [16] (PDF)

Coping [17]

Additional Resources

National Cancer Institute: What to Do When You Feel Weak or Tired [18]