Fatigue is by far the most common symptom affecting people with cancer. For some, it is the most distressing symptom. At its worst, cancer-related fatigue is a draining, ongoing exhaustion that limits one's ability to enjoy life and do activities.
Many patients with cancer don't tell their doctors about their fatigue. They incorrectly believe nothing can be done to help them. The good news is that there are ways to limit fatigue and its adverse outcomes.
Many factors have been linked to fatigue. Examples of such factors include anemia, cancer, cancer treatments, and depression. Because of so many factors, it can be hard for a doctor to know the exact source of a patient's fatigue.
Cancer-related fatigue generally occurs when cancer spreads to bone marrow and causes anemia. Anemia is a decrease in red blood cells, which carry oxygen to cells. Less directly, cancer may cause fatigue when it creates toxic substances that disrupt cell functions. Fatigue is an early symptom of leukemia—a cancer that starts in bone marrow. It may also occur among people with lung and other cancers that affect breathing.
Cancer treatments also are known to reduce energy. Examples of such treatments include chemotherapy, radiation, bone marrow transplants and biologic therapies. Cancer drugs not only attack cancer cells, but strike at fast-growing healthy cells including red blood cells. As a result, cancer treatments can induce anemia which can cause fatigue. Fatigue often lessens or stops when treatment ends, but sometimes it lingers.
Other factors linked to fatigue include:
- Depression and anxiety,
- Sleep problems,
- Poor nutrition,
- Medications (such as antihistamines, antidepressants, narcotics and anti-nausea drugs), and
- Other health conditions.
Tell your treatment team about your fatigue. They can suggest ways to help you feel better. There are many ways to treat or manage cancer-related fatigue, such as:
- Increasing activity. It may require much effort to get up and move around, but increasing your physical activity may reduce fatigue. Studies show that cancer patients who exercise are less tired and depressed. They also sleep better than patients who don't exercise. (See "Exercising During Cancer Treatment" for more tips.)
- Nutrition counseling. Many patients aren't able to eat normally and lose weight. This may be due to treatment-related nausea, vomiting, and lack of appetite. Ask your doctor to refer you to a nutrition counselor. A nutrition counselor is an expert in healthy drinks and foods. This expert can work with you to ensure that you are getting enough calories, fluids, protein and other nutrients to help prevent fatigue and increase energy.
- Psychosocial measures. Behavioral techniques including cognitive therapy, relaxation, counseling, social support, hypnosis, and biofeedback can decrease fatigue. Therapies that aim to educate patients about fatigue and related factors help reduce fatigue. Support groups and journaling may also decrease fatigue. Contact the American Cancer Society or the Cancer Support Community to locate support groups in your area.
- Rest. It is important to save energy and take on only the most important activities when you have the most energy. Keep a log of the times when you are most and least tired. Move around and exercise when you are well rested and have the most energy. Be realistic about your limits and don't be hard on yourself. Also don't be too shy or too proud to accept help. Let others take care of chores, driving, cooking, and so forth when you are not up to it.
- Distraction. Try "escaping" from your fatigue by doing things you enjoy. Listen to your favorite CD. Read a juicy novel. Relax with friends. Watch a funny movie.
- Sleep therapy. Many people with cancer suffer from disrupted sleep patterns. Using relaxation methods, limiting caffeine to the morning, keeping naps short, and having good sleep habits improve sleep. Good sleep habits include going to and getting out of bed at the same times each day.
- Medications. Little research has been done to test medications for fatigue in patients with cancer. Your doctor may prescribe medication based on the causes and severity of your fatigue. Treatment of anemia with erythropoietin may help decrease fatigue. Psychostimulants, such as methylphenidate or modafinil, may be considered. Antidepressants aren't recommended to treat fatigue in cancer patients although they may help treat depression and anxiety.
More information on fatigue can be found in the NCCN Clinical Practice Guidelines in Oncology for Cancer-Related Fatigue. These guidelines were written for doctors. If you have questions, your doctor can consult these guidelines and provide an answer.