Contact our breast care nurses 0808 800 6000

Cognitive impairment (chemo brain)

Cognitive impairment, sometimes called ‘chemo brain' or ‘chemo fog’ can make it harder to concentrate. Find out more about the symptoms and getting more support.

1. What is cognitive impairment?

During and after breast cancer treatment, you may find it difficult to concentrate or feel more forgetful. This is sometimes called ‘chemo brain’ or ‘brain fog’.

Although it’s commonly called ‘chemo brain’ it can affect anyone going through cancer treatment even if they do not have . Your treatment team may call it cognitive impairment.

Cognitive impairment usually improves over time, but for some people it can continue, especially if the treatment causing it is ongoing.

Having difficulty concentrating or remembering things can affect your daily life.

2. What causes cognitive impairment?

It’s not known exactly what causes changes to memory and concentration following cancer treatment.

Some experts think chemotherapy may speed up the normal ageing process.

There’s some evidence hormone therapies, such as letrozole, can also cause symptoms of cognitive impairment. The evidence for this is mixed and more research is needed to understand the causes.

Other factors may contribute to cognitive impairment, such as:

3. Symptoms of cognitive impairment

Symptoms vary from person to person and can come and go.

You may notice these in day-to-day activities or they may not be obvious.

Some common symptoms include:

  • Short-term memory loss
  • Finding it difficult to concentrate or think clearly
  • Finding it difficult to do more than one thing at a time
  • Being unable to put thoughts into action
  • Being less organised than usual
  • Having trouble finding the right words or finishing sentences
  • Feeling tired (fatigue) or lacking energy

If you have these symptoms talk to your treatment team. They can assess you and provide support to help manage and improve them.

4. Coping with cognitive impairment

There’s limited evidence about whether particular medicines will help improve cognitive impairment, and research is ongoing. Unless you’re taking part in a clinical trial it’s unlikely you will be prescribed any medicine.

However, there are some things you can do to help manage your symptoms:

  • Keep a diary – this may help you notice triggers, for example it may be worse when you’re hungry or tired
  • Write things down – use a calendar, your phone alarm or a notepad to write down reminders
  • Plan ahead – prepare for big events or busy days in advance
  • Meal plan for your week ahead
  • Focus on one task at a time
  • Eat a healthy balanced diet and keep yourself hydrated
  • Brain training – keep your brain busy by using brain training games and apps
  • Regular physical activity – focus on exercise you enjoy such as walking, swimming or yoga
  • Mindfulness – many people find taking time out to practise mindfulness or relaxation techniques can help
  • Use a pill box if you’re taking regular medications

It can help to talk to people about cognitive impairment and how it’s affecting you. They may be able to offer support and practical help, such as food shopping and meal planning.

Lifestyle factors, such as difficulty sleeping or stress, can also make the symptoms of cognitive impairment worse. Talk to your treatment team about how to manage these.

Some people find different brands of treatments, such as hormone therapies, can make cognitive impairment better or worse. You could keep a record of the brand you’re prescribed and symptoms you get. If you find a brand that suits you, you could ask your GP or pharmacist if you can continue to have this.

Some people find CBT (cognitive behavioural therapy) helpful. CBT is a talking therapy that can help you change patterns of thinking and behaviour. You can find out more about CBT on the NHS website.

5. Cognitive impairment and work

As cognitive impairment can affect your memory and concentration, you may find it difficult to carry out your usual role at work. This can lead to you feeling stressed, which can make the symptoms worse.

If you’re worried about work or returning to work, speak to your employer about reasonable adjustments – such as a temporary change to your work hours or more regular breaks.

Occupational health services might help employees who have cognitive impairment. Your human resources team or manager may be able to tell you about these and suggest other sources of support.

If you’re self-employed, you can call Macmillan Cancer Support on 0808 808 00 00 to find out what support is available. They also have information on self-employment and cancer.

6. Further support

Cognitive impairment can be difficult to cope with, and many people feel frustrated and as if they’re not in control.

Through our online forum, we’re with you every day. For every experience. Every step of the way.


Was this helpful?

Was this helpful?
Please tell us what you liked about it.
Please tell us why.
We’re sorry you didn’t find this helpful.
Please do not include personal details and be aware we cannot respond to comments.

Quality assurance

This information was published in January 2023. We will revise it in January 2025.

Get support

  • support-cta-icon-telephone

    Call our free helpline

    If you have any concerns about breast cancer, or just want to talk, our specialist nurses are here for you.

    Lines open: Monday to Friday - 9am to 4pm; Saturday - 9am to 1pm

  • support-cta-icon-email

    Explore ways to talk to our nurses

    It can be difficult to talk to someone in person about breast cancer concerns. Explore other ways you can ask a question.

2937.challengers wall 10.jpg
Support service

Someone Like Me

You never have to face breast cancer alone. Find somebody who understands what you're going through with Someone Like Me.

Share this page