Radiotherapy tiredness | Cancer Research UK
Cancer Research UK on Google+ Cancer Research UK on Facebook Cancer Research UK on Twitter

Radiotherapy tiredness

Nurse and patients talking about cancer

This page tells you about tiredness caused by radiotherapy. There is information about


Why you may feel tired

You may feel very tired during your radiotherapy treatment. This is because the body has to repair damage caused by the radiotherapy to healthy cells. It is important to drink about 3 litres of water a day if possible while having treatment. Hydration helps the body to repair the radiotherapy damage better. If you have to travel to your treatment each day, you may get even more tired. 

Tiredness tends to creep up on you as you go through your treatment. So you may not feel tired at the beginning of your course, but you are very likely to by the end. You may feel like having a sleep 1 to 2 hours after each radiotherapy treatment. This tiredness is called fatigue and you may also feel weak and as though you have no energy.

Tiredness can still be a problem for some months after your treatment has finished. Our tiredness and cancer section has tips on treating it. 


Tips for boosting or saving energy

There are many things that you can do in your everyday life that help you use up less energy. Taking short cuts on some things or getting help from other people can help you feel less tired. 

Some research into treating fatigue shows that it is important to balance exercise with resting. Try to schedule in a short walk each day. You may find that you can gradually increase the distance. Pick the time of day when you are feeling least tired. Remember though, that however far you walk, you'll have to walk the same distance back, so try not to overdo it.

Try some of the following to help save your energy

  • Try not to rush
  • Plan ahead where possible
  • Give yourself plenty of time to get places
  • Don't travel in peak hour traffic if you can avoid it
  • Put chairs around the house so you can stop and rest if necessary
  • Sit down to dry off after a bath or put on a towelling dressing gown and let that do the work
  • Get an occupational therapist or social worker to get hand rails put up in your bathroom to hold on to when getting in or out of the bath or shower
  • Prepare your clothes and lay them out in one place before you dress
  • Sit down to put most of your clothes on
  • When dressing, try not to bend down too much – bring your foot up on to your knee to put socks and shoes on
  • When dressing, fasten your bra at the front first and then turn it to the back
  • Wear loose fitting clothes
  • Wear clothes with few buttons to do up
  • Where possible do household tasks sitting down, such as peeling vegetables or ironing
  • Choose clothes that don't need ironing
  • Use a duster on a long stick and sit to do your dusting
  • Write a list of shopping and go when the supermarket is not busy or have food delivered
  • If you have children, play games with them that can be done sitting or lying down, such as board games, reading books and drawing pictures
  • Ask family and friends for help with things like shopping, housework, gardening, and collecting the children from school
  • You may find it easier to have lots of small meals, rather than the usual 3 meals a day
  • Have plenty of nutritious snacks and drinks in stock that you can have whenever you feel like eating
  • Don't forget to do things that you enjoy – this may take your mind off things a bit and make you feel more relaxed
  • Buy ready made meals that you can quickly heat up rather than making food from scratch
  • You can buy ready peeled vegetables to save even more energy

Tiredness after brain radiotherapy

People having radiotherapy for brain tumours can be particularly affected by tiredness and it can be worse if you are also taking steroids. The tiredness often reaches its maximum 1 to 2 weeks after the end of treatment. A small number of people are asleep virtually all day for a short time after a long course of radiotherapy to the brain. You may hear this called somnolence syndrome.


More information about radiotherapy

We have detailed information about external radiotherapy and internal radiotherapy in this section.

There is also detailed information about the side effects of radiotherapy.

You can phone the Cancer Research UK nurses on freephone 0808 800 4040. The lines are open from 9am to 5pm, Monday to Friday. They will be happy to answer any questions that you have.

Our general organisations page gives details of people who can provide information about radiotherapy. Some organisations can put you in touch with a cancer support group. Our cancer and treatments reading list has information about books, leaflets and other resources about radiotherapy treatment.

If you want to find people to share experiences with online, you could use Cancer Chat, our online forum.

Rate this page:
Submit rating


Rated 5 out of 5 based on 54 votes
Rate this page
Rate this page for no comments box
Please enter feedback to continue submitting
Send feedback
Question about cancer? Contact our information nurse team

No Error

Updated: 2 May 2014