Feeling exhausted and lacking energy for day-to-day activities is a common side effect of radiation therapy. During treatment, your body uses a lot of energy dealing with the effects of radiation on normal cells.

Fatigue can also be caused by travelling to treatment and appointments. It usually builds up slowly during the course of treatment, particularly towards the end, and may last for some weeks after treatment finishes. Many people find that they cannot do as much as they normally would, but others are able to continue their usual activities.

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Tips for managing fatigue

  • Listen to your body. If you feel tired, rest.
  • Try to spread activities out through the day.
  • Ask family and friends for help, e.g. with shopping, housework and driving.
  • Take a few weeks off work during or after treatment, reduce your hours, or work from home. Discuss your situation with your employer.
  • Do some light exercise, such as walking. Regular exercise may give you more energy and make you feel less tired. Talk to your treatment team about suitable activities for you.
  • Limit caffeinated drinks, such as cola, coffee and tea. While caffeine may give a burst of energy, it can make you feel jittery and irritable, and cause insomnia and dehydration.
  • Limit your alcohol intake. Also try to quit smoking if you smoke.
  • Eat a healthy, well-balanced diet, and don’t skip meals.

This information was last reviewed in December 2017
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