1. Health

Cancer Fatigue

What Causes Cancer Fatigue and How to Fight It


Updated October 31, 2012

Fatigue is the number one reported side effect of cancer treatment. When you have cancer, everyday tasks that may have seemed effortless before like showering or eating can feel like they require enormous amounts of energy to complete. Cancer-related fatigue is described as "sudden." The fatigue comes on suddenly and can be debilitating.

Signs You May be Fatigued

One of the most common misconceptions about fatigue is that a person must experience severe exhaustion to be considered fatigued. Actually, fatigue can range from moderate tiredness to exhaustion with bursts of energy in between. Fatigue can occur in cycles and does not have to be constant.

Feeling tired even after resting is a good indicator that you may be suffering from fatigue. Feeling moody or irritable, having trouble concentrating, and finding daily living activities, such as bathing, to be tiresome may also indicate that you are suffering from fatigue.

The Causes of Cancer Related Fatigue

It can be hard to pinpoint the exact causes of fatigue during cancer treatment. The source could be treatment itself or be a result of the emotional investment of a cancer diagnosis. Possible causes of cancer-related fatigue include:
  • side effect of chemotherapy
  • anemia
  • undergoing more than one type of cancer treatment like radiation therapy and chemotherapy
  • nutritional deficiencies due to loss of appetite or stomach upset caused by treatment
  • depression

How to Combat Cancer Fatigue

Combating fatigue is easier than you may think. Just a few small changes in your daily schedule can make a big difference.
  • Plan your day ahead of time to include periods of short rest, like naps and relaxing.

  • Exercise is one of the best way to fight fatigue. Take a short walk, use a stationary bike, or even doing yoga can raise your energy level. Talk to your doctor prior to any exercise routine to see what is appropriate for you.

  • Drink plenty of fluids. Dehydration is a major source of fatigue. You may be tempted to reach for caffeinated drinks like energy drinks, coffee, and soda, but these are all dehydrating. The burst in energy you experience from drinking these beverages is only temporary and will leave you with less energy in the long run.

  • Delegate responsibilities to family members, like cleaning, cooking, or bill paying.

Most importantly, talk to your physician about your fatigue. A simple blood test can reveal an underlying problem that may be causing your fatigue, such as in anemia.

When to Call the Doctor

If fatigue worsens, prevents you from walking or maintaining balance, or if you are so tired you have trouble waking or are too sleepy to get out of bed, you need to contact your physician. Fatigue can be managed and treated, but only if your physician is made aware of it. This severe type of fatigue is not normal and should be evaluated by your doctor.


Hoffman, M. et al. Cancer-Related Fatigue: The Scale of the Problem. The Oncologist. 2007. 12:4-10.

Tannock, Ian, Tim A. Ahles, Patricia A. Ganz, Frits S. van Dam. "Cognitive Impairment Associated With Chemotherapy for Cancer: Report of a Workshop." Journal of Clinical Oncology 22, No 11(2004): 2233-2239.

  1. About.com
  2. Health
  3. Cancer
  4. Treatment of Cancer
  5. Chemotherapy
  6. Chemotherapy Side Effects
  7. Cancer Fatigue - How to Cope

©2014 About.com. All rights reserved.

We comply with the HONcode standard
for trustworthy health
information: verify here.