Defend against the drain on your energy

People with cancer often experience fatigue, and they describe it using a variety of words, including “exhausted,” “weak” and “worn out.” However it’s described, the fatigue related to cancer and its treatment is different from the fatigue that healthy individuals occasionally feel. It usually lasts longer, is more severe and is unrelieved by sleep. Managing fatigue is an essential part of your health care, so be sure to talk to your doctor about your fatigue.

What causes fatigue?

Several factors may cause cancer-related fatigue, including the cancer itself. Cancer can alter your hormones, weaken your muscles and trigger other changes in your body, which all may lead to fatigue. Various types of treatments can also contribute, primarily because the body needs extra energy to repair the healthy tissues damaged during treatment.

In addition, other treatment side effects (such as pain, nausea and vomiting) can cause or worsen fatigue, and certain medications to relieve those side effects can lead to fatigue as well—as can the interaction of two or more medications. Another common contributor to fatigue is anemia, a low level of red blood cells. (See Anemia for a more complete discussion of anemia.) Depression, stress, poor nutrition, other medical conditions, changes in your sleep/wake cycles, and reduced activity may also cause or worsen fatigue.

Who is at risk for fatigue?

Almost everyone treated for cancer experiences fatigue at some point, regardless of the type of cancer they have or the type of treatment they receive. How fatigue will affect you depends on several factors, including your age, general health, types of treatment and your normal level of activity.

When does fatigue occur?

Fatigue can strike at any time, but the type of treatment you receive plays a large role in when it occurs. If you’re having surgery, the effects of anesthesia, the use of strong pain relievers, and the limitations placed on your activity can make you feel tired and weak for a few days to a few weeks after surgery.

If you’re receiving chemotherapy, you’ll probably feel the most tired about two hours after each treatment. Fatigue typically peaks within a few days following the beginning of a chemotherapy cycle and then gradually gets better until the next treatment cycle begins. Radiation therapy takes longer to produce fatigue; a feeling of being tired and weak usually starts a few weeks after treatment begins and gradually diminishes after treatment ends.

Fatigue may be fairly constant or may occur from time to time. Some people feel less tired once treatment stops, and others may feel tired for several more months.

How is fatigue managed?

Managing fatigue largely depends on the cause. For example, if your doctor determines that a certain drug or drug interaction is causing your fatigue, you may need to change or stop taking those drugs or supplements. However, if the cause is unclear, you may need to try something more general, such as increasing your activity level. While most people think more rest will help, the opposite is actually true; regular exercise (such as walking or riding a bike) is the best way to help manage and reduce symptoms of fatigue. The techniques listed in Table 1 may also help.

Table 1. Ways to manage fatigue related to cancer treatment
Conserve energy
- Set priorities for activities and do only what’s most important
- Schedule important activities for times of the day when you have the most
- Sit down when washing or grooming
Balance activity and rest
- Participate in regular physical activity, such as walking, yoga or bike riding
- Take frequent rest periods or naps, but limit each nap to 45 minutes
- Get eight hours of sleep each night
Engage in activities that provide relaxation or distraction from fatigue
- Perform deep-breathing exercises
- Use imagery techniques
- Read, listen to music and play games
- Pray or meditate
Consider alternative therapies
- Getting a massage may help you relax
- Ask your doctor if acupuncture or acupressure may be right for you
Seek relief from other symptoms
- Ask your doctor for help managing symptoms that may contribute to fatigue,
  such as pain, nausea, vomiting and depression
Maintain adequate nutrition
- Eat a well-balanced diet to help promote healing and restore your energy

If your fatigue is severe, your doctor may prescribe a psychostimulant drug, such as modafinil (Provigil), armodafinil (Nuvigil), methylphenidate (multiple brand names) or dextroamphetamine (Adderall, Dexedrine), for a short period of time. These drugs can help improve your alertness and raise your energy during the day, while also decreasing fatigue. In addition, they can counteract the drowsiness caused by some opioids.

If you plan to work during treatment, talk to your supervisor before your treatment starts about the possibility of fatigue and ways you can handle it, such as taking time off or scheduling important tasks for times when fatigue may be at its lowest.

Also, ask about a referral to a cancer rehabilitation facility – before treatment if possible – to learn about proven techniques that may reduce the effects of fatigue.

When should I talk to my doctor about fatigue?

Describe your fatigue at every office visit, and call your doctor immediately if you have any of the following symptoms:

  • Confusion
  • Dizziness or loss of balance
  • Extreme tiredness that forces you to stay in bed for more than 24 hours
  • Fatigue that has gotten worse or a sudden decrease in energy level
  • Feeling of breathlessness (being out of breath) or of a racing heart after mild activity