Life After Cancer

How to deal with fatigue from breast cancer treatment

Posted by Dr Jane Clark on 02 July 2021

woman asleep at her desk with her laptop open

This article is adapted by Dr Jane Clark from an article originally written by Jane and Dr Peter Harvey. See our introduction for a background on this series of articles.

Of all the many consequences of cancer treatment, fatigue may be one of the most common and the most difficult to deal with. It is hidden from the view of others and is often difficult to describe.


Those people who have not experienced it may simply think of it as a sort of over-tiredness which will be solved by a few good nights’ sleep. But as you know it’s not like that.

Cancer-related fatigue is not like anything you have experienced before.

It’s like hitting a brick wall. And it’s not just a physical tiredness. I found that the mental and emotional fatigue hit me harder than my body just feeling tired. It knocked me for six and I had to strip life back to the essentials to get through each day, just as everyone’s expecting you to be full of positivity because you’ve finished treatment.

Even the simplest of tasks feels as if you are wading through treacle. Because it doesn’t show on the outside, both you and those around may feel that it’s something that you should be able to get over simply by trying that bit harder.

The trouble with that is you are trying as hard as you can, and you don’t have the energy to put in any more effort. If you had a seriously broken leg and were hobbling around on crutches, not only would others see your predicament, but you would as well and wouldn’t expect yourself to have the mobility of someone without a hulking great plaster cast on your leg.

With fatigue you have the equivalent of a plaster cast around the whole of your body which hinders you from doing as much as you want.

What research there is into fatigue suggests that up to 90% of patients report some degree of it during their treatment – particularly chemotherapy.


After the treatment has finished, it is suggested that about a third of people report some degree of continuing fatigue. A long-term study of women treated for breast cancer suggested that around 20% had problems with fatigue up to ten years after treatment was completed.


So how do you deal with it? Perhaps the first and most important thing is to acknowledge that this is real, that you are not slacking or not trying hard enough and to stop telling yourself off.

Secondly, it is a helpful general rule to break tasks into easily manageable pieces – ‘bite-size chunks’. Use a walk to the local shops as an example. Before your treatment you may have been able to do this without a problem. Now it’s an uphill struggle and you either can’t face it or you come back exhausted.


Don’t even attempt to do the whole journey yet. Work out how far you can walk without over-tiring yourself – say it’s 100 metres. Then set yourself the target of walking 50 metres (which, of course makes 100 metres there and back).

You may do this easily and feel that you could have done more. Great! It’s always better to feel that you could have done more than come back feeling that you have done too much. You can always walk further tomorrow.

Each time you try it and feel OK then walk a bit further the next time until you get to the shops and back without exhausting yourself.


It might be helpful to think about this using a sporting example. If you were a top-class athlete who had injured themselves, you would not expect (nor would be allowed) to get back to top form straight away. You would be put on a gradual programme of exercise and jogging before even thinking about sprinting.

It very much the same with getting back to doing things after cancer treatment. You cannot expect to get back to doing ordinary things straight away – you have to allow yourself to build up your strength bit-by-bit, literally one step at a time.

There is some evidence to suggest that mild graded exercise can help with exercise capacity and muscle capacity, although the benefits are less clear-cut in the case of fatigue.

There is also evidence that cognitive behaviour therapy can be of help. Before taking any of this on, however, it is important to get appropriate advice from your care team.


This is a difficult question to answer. One of the features of severely depressed mood is lack of energy – a feeling rather like that experienced by people with fatigue.

However, an important difference is that with depression there is often an additional lack of motivation – rarely present with post-treatment fatigue. You may want to do something but simply feel that you haven’t the energy to do it. One of the effects of fatigue is a sense of frustration and annoyance with yourself which can, in turn, lead to a feeling being heartily fed-up and down. And because you are fatigued, you cannot do the things you did before which gave you a boost – going out shopping, meeting friends, hobbies and such like (pre-pandemic anyway!).

This lack of opportunity to enjoy yourself as you used to, can also lead to feelings of despondency and lowered mood. So, it can be a bit circular, with each aspect – fatigue and low mood – amplifying the other. That’s one reason for not telling yourself off unduly for not trying hard enough or expecting yourself to be living at the same pace that you did before the treatment started.


Taking on a gradual programme of activities, a bit at a time, step-by-step, can increase your sense of doing something and getting somewhere. Dealing with the seeming slowness of your progress is an important aspect of regaining your sense of mastery and control.

Dr Jane Clark, Consultant Clinical Psychologist

Next 11: Dealing with Chemo Brain

The information and content provided in this page is intended for information and educational purposes only and is not intended to substitute for professional medical advice.

June 2021

©️ 2023 Jane Clark and Peter Harvey. With quotes from the Ticking off Breast Cancer website creators (now Future Dreams). All rights reserved.


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