Fatigue, or the feeling of extreme tiredness, is the most common side effect of cancer treatment. Symptoms of fatigue include not being able to focus, not being able to remember things, mood changes, and a general feeling of being tired. Cancer-related fatigue has many causes. Some of them may be cancer itself, anemia, poor nutrition or lack of exercise.



  • Being in active cancer treatment (chemotherapy or radiation)
  • Taking medications for:
    • Pain
    • Depression or anxiety
    • Allergies
    • High or low blood pressure
  • Taking Tamoxifen or Aromatase Inhibitors (such as Aromasin, Femara, Arimidex)

If you can, take these medicines at night before you go to bed. This may help you have less daytime fatigue. In some cases, it is important to find the time of day to take medicines that will allow you to rest at night and not be as tired during the day.

Some medicines may keep you awake. For example, some women find they cannot sleep after taking Tamoxifen, while others feel extremely tired. Another medication that in some cases interferes with sleep is a water pill (diuretic). Since these medications make you have to go to the bathroom, it’s important to not take these at bedtime.

Pain medicine may cause drowsiness. Drowsiness should go away after about three days when your body gets used to the medicine; however, it may not. It is important to notice how you react to these medications and adjust when you take them during the day, if you can.

Review both prescribed and over the counter pain medicines with your doctor to see if any changes can be made to decrease fatigue.



Mental fatigue affects your mood. It may also affect how well you can organize your day and your ability to focus. People who have mental fatigue report feeling weighed down. If you are having mental fatigue, here are some tips to help you cope with its effects:

  • Make a list of what you plan to do each day. Include only the things that must be done that day. Keep a second list of things you’d like to do if you have the extra energy. Save your energy for things that mean the most to you.
  • Check your goals. Being careful and realistic in what you choose to do will reduce mental as well as physical fatigue.
  • Learn to pace yourself. You can do more by spreading what you need to do over the entire day. Take rest breaks as you need.
  • Enjoy what you are able to do, even small things such as a short walk or taking a shower.
  • Take a mental break between activities and walk or sit quietly in a peaceful setting. Being in a peaceful setting can help counter mental fatigue.
  • Listen to your body and rest when you need to. Don’t take naps in the late afternoon or evening since this may affect your nighttime sleep.
  • Reduce stress and take care of yourself in ways you find most relaxing (e.g., pampering yourself, meditating, praying, deep breathing)
  • Keep a fatigue journal of your progress. Note when fatigue occurs, lifts, or lingers. This can help you make a realistic daily schedule.
  • Talk to your family about your fatigue. If your family does not know about your fatigue, it can lead to communication problems, anger, and feelings of guilt.
  • Remind yourself: Cancer Fatigue is real! – It is not in your head and you are not alone.



If you want to try exercise to fight fatigue or just to stay healthy, here are a few tips that may help. Talk with your doctor or nurse to find out if there are any special safety measures you should take.

  • Exercise within your own limits and set realistic goals.
  • Start with regular, light exercise such as walking. Begin with 5-10 minutes, once or twice every other day. Over time increase how long you walk. Try to do a little something each day. If you feel very tired, take the day off.
  • Do something that you like to do. Decide on something that you enjoy, that will work your heart, and make you stronger and more flexible.
  • Try new kinds of exercises, then choose those that help to keep or increase your energy.
  • Do not bounce or jerk your arms when doing any exercise. Your movements should be slow and smooth.
  • Wear comfortable clothing, such as a loose-fitting cotton shirt and sweatpants, shorts, or a full skirt. Try to avoid tight outfits especially those with elastic in the sleeves.
  • Stop exercising if you have nausea, feel dizzy, have an irregular heartbeat, have pain, or any shortness of breath during exercise.
  • Keep a diary of your activity. Include how you felt during and after your exercise sessions as well as how your sleep was affected.
  • On days you feel good, exercise a little longer; on days you feel tired, shorten your exercise schedule or select an easier activity, such as stretching or a gentle movement program.
  • If exercise is not possible try to plan some gentle activity in your daily schedule and slowly increase it at your own pace.
  • Include stretching and relaxation practices at the end of each exercise session.
  • Lie on your bed to stretch if you can’t get down on the floor. Choose a bed with a firm mattress.
  • Find an exercise partner who will help keep you motivated.
  • Staying healthy means making exercise a part of your routine. Exercise should include both aerobic and strength training exercises, so change it up with different exercises for different days of the week and create new routines every few months.



Remember, you need to eat enough food so that your body can have the energy to heal itself.

The National Cancer Institute recommends eating a variety of foods every day, including:

  • Fruits and vegetables. Raw or cooked, these give you vitamins, minerals and fiber.
  • Whole grains, such as cereal, bread and pasta, give you vitamins, minerals and fiber.
  • Low fat dairy products. Milk, cheese, yogurt and ice cream supply protein, calcium and several vitamins.
  • Lean meats. Poultry or lean cuts of beef or pork supply protein.

Variety not only makes what you eat more interesting but allows your body to get the different nutrients it needs. For instance, if you eat many servings of the same fruit day after day, you may not be getting all the nutrients that you need.  It is important to focus on your overall dietary pattern, not a specific food. No single food, vitamin, mineral, spice, herb or supplement can prevent or cure cancer!



  • Start your day with a good breakfast. Try to include at least 1/3 of your protein requirements in this meal, such as eggs or lean meats. Unlike carbohydrates (toast or cereal), protein provides you with long lasting energy and will help you keep your energy throughout the day.
  • Eat plenty of iron rich foods, like lean red meats, poultry, dark green vegetables and dried fruits.
  • Eat several small meals rather than three large meals.
  • Stay hydrated. Dehydration can make you feel more fatigued.
  • Eat when you are hungry. Try to take advantage of the times when your appetite is best.
  • Avoid caffeine and white or refined sugars (cookies, cake, or candy). While these products are OK in moderation (they may even give you a quick boost!), they tend to cause a rapid rise and fall in your blood sugar and will leave you more tired.
  • Limit foods high in fat, salt, and sugar. Limit alcohol intake, particularly close to bedtime. This can cause waking during the nighttime and not allow you to get the deep sleep that you need. Limit foods that are smoked or pickled.

If you find you are not eating because you are too tired to prepare your meals:

  • Consider having pre-packaged / frozen meals on hand.
  • Ask friends and family for help with meals.
  • Prepare larger amounts when you do cook and freeze extra food in single serving containers for easy reheating.
  • Use paper plates and cups to cut down on cleanup.
  • Keep a diary of what and when you eat every day and how it affects your fatigue.



If you do want or need to keep on working during your cancer treatment, here are some tips to help make your work less tiring.

  • Work with your boss to set sensible goals for yourself and what you can manage now. Tell your boss about how tired you feel. Be sure your boss knows that you are doing all that you can so that you will have more energy. Also, make sure your boss knows that you would like to remain a useful worker.
  • Ask for a change in your current job duties. Things that your boss can do to help include:
    • Change your hours. It may be that you can go to and from work at less busy times (outside rush hour) or perform some of your duties from home.
  • Take a short break now and again to lie down and rest if needed.
  • Learn a new job skill that might be less stressful on your body and mind.
  • Plan your workload to use your high energy times wisely.
  • Minimize unnecessary movements by parking your car close to the building and trying to set up your work area so that you are close to the things that you use a lot.
  • Talk openly with your boss and fellow workers about feeling tired because of cancer or treatment. This may help them better understand your change in energy level or work schedule. The more they know, the better they can support you.
  • Do not feel embarrassed about asking others for help. Keeping others in the loop about how you feel and what help you need prevents confusion, mistrust, and anxiety.
  • Talk to your company’s human resources department to find out if your health plan provides referrals that can assist you in dealing with your fatigue. They might include a nutritionist, physical or occupational therapist, exercise physiologist, or mental health or alternative health practitioner.
  • Get to know your own company’s rules about sick leave, disability, flexible work times, and options to retrain.
  • Know the provisions of the Americans with Disabilities Act and the Family Medical Leave Act so that you know your rights in the workplace.
  • If you are self-employed, it can be useful to talk to the Department of Social Security about benefits that you may be able to claim.

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This information was reviewed by Forge’s Client Services Coordinator Janet Dees, RN, BSN, MBA, who specializes in helping breast cancer patients, survivors, and those who love them navigate their unique survivorship journeys. If you have any questions or concerns, please contact Janet at (205) 990-5367 or [email protected]. Si hablas español y quieres más información, por favor contacta a Yadira Robayna, al (205) 990-5375 O al [email protected].