Tiredness (fatigue)

Fatigue is feeling very tired or exhausted most, or all, of the time. Most people who have cancer will experience fatigue at some point.

What is fatigue?

Fatigue is a feeling of tiredness or exhaustion. Cancer and cancer treatments can cause fatigue. Fatigue in people with cancer is sometimes called cancer-related fatigue or CRF. CRF is a very common problem.

Fatigue in people with cancer can be more severe. They may get tired more quickly after less activity and feel exhausted even if they are getting enough rest and sleep.

Fatigue affects everyone differently. It can vary throughout the day, and each day may be different. For most people, fatigue gets better after treatment finishes. But for some it may continue for months or sometimes years.

Causes of fatigue

We do not fully understand what causes cancer-related fatigue (CRF). There may be many reasons for it, including:

  • The cancer itself

    Sometimes, the cancer itself may cause fatigue. Cancer may affect the levels of cytokines in the body. Cytokines are a type of protein. They help control some of the things that cells do. Research has suggested that cytokines may be involved in cancer related fatigue. Some cancers may reduce the number of red blood cells (anaemia). Others can cause a build-up of fluid (ascites) or changes in hormone levels, which can cause fatigue.

  • Cancer treatments

    Some cancer treatments can cause anaemia, which can cause fatigue. But doctors are still learning about why cancer treatments can cause fatigue. It might be because the body’s immune system is affected and the body needs extra energy to repair and heal. Or fatigue could be caused by a build-up of chemicals as the cancer cells are destroyed. We have more information on individual treatments and their effects.

  • Anaemia

    Anaemia is when you have a low number of red blood cells. Red blood cells contain a protein called haemaglobin (Hb) which carries oxygen around the body. If you do not have enough red blood cells, the body does not have enough haemaglobin. This reduces the amount of oxygen your body gets which can make you feel very tired. You may also feel breathless, dizzy and light-headed, and have chest tightness.

    You will have a blood test to check the level of haemoglobin in your blood. The main treatment for anaemia is a blood transfusion. Other treatments include erythropoietin or an iron infusion (drip). Your doctor or nurse can explain more about these treatments.

  • Eating problems

    Our bodies get energy from the food we eat. You may get tired if your body does not get enough food, or if there are changes to the way your body is able to use food. Some people lose weight even if they are eating a lot, because of the effect of the cancer on the body. We have more information about eating problems and coping with eating difficulties. 

  • Pain

    Having cancer does not mean you will have pain. But if you do have pain, it can cause fatigue. The best way to deal with fatigue caused by pain is to manage the pain. Talk to your GP, cancer doctor or specialist nurse about how it is affecting you.

  • Other health problems

    Other health conditions like diabetes, heart problems or low thyroid function can also cause fatigue. Having a cancer diagnosis and other health conditions may make the fatigue worse. Some medicines for other health conditions can also make you feel tired.

  • Trouble sleeping
    Sleep problems when you have cancer are very common. Losing a night of sleep will not have any effect other than making you feel tired the next day. But trouble sleeping (insomnia) over a long period of time can lead to fatigue, low mood and difficulties with concentration and making decisions.

  • Your feelings

    Anxiety, depression, stress and tension can make fatigue worse. You may find it helpful to talk about how you feel with a partner, family member or close friend. Some people find it helpful to talk to people at a local support group or join an online support group. Macmillan’s Online Community is a place you can talk to others who understand what you are going through. 


Effects of fatigue

For some people, cancer-related fatigue can affect all aspects of daily life. For others, the fatigue is very mild and does not affect them as much.

Some of the more common effects of fatigue include:

  • difficulty doing simple things, such as getting dressed
  • feeling weak and that you have no energy or strength
  • difficulty concentrating and remembering things
  • difficulty thinking, speaking or making decisions
  • feeling breathless after doing gentle activity
  • feeling dizzy or lightheaded
  • difficulty sleeping (insomnia) or sleeping more than usual
  • losing interest in sex
  • feeling low in mood and more emotional than usual.

Fatigue can affect your daily activities, social life and relationships, your work or studies, but there are things you can do to help. Getting support from your healthcare team may help prevent or relieve some of these effects. It may also help improve your quality of life.

Assessing fatigue

How fatigue is managed depends on what is causing it. Before it can be treated, it is important that it is properly assessed.

A fatigue assessment is usually completed when you are first diagnosed with cancer, during your treatment and after you have finished treatment. But it is important to tell a member of your healthcare team if you have fatigue at any time

Your cancer doctor, specialist nurse or GP will ask you some questions, or they may use a questionnaire. Your specialist nurse may assess your fatigue as part of a holistic needs assessment (HNA). An HNA is a simple questionnaire that helps identify what your main concerns are.

You may be asked:

  • when the fatigue started, how long it lasts and what makes it better or worse
  • how the fatigue affects your daily activities
  • how severe the fatigue is on a scale of 0 to 10, where 0 is no fatigue and 10 is the worst possible fatigue.

They may talk to you about treatment side effects, your emotions, symptoms such as pain or anaemia and any other medical conditions.

Your healthcare team will regularly check how you are feeling, as fatigue can continue months or years after treatment. This is called a late effect of treatment. Your cancer team can tell you about the risk of developing any late effects.

Managing fatigue

Cancer-related fatigue (CRF) affects everyone differently. It may take time to find out what works for you. Talk to your cancer doctor, specialist nurse or GP before you make any big changes. They will make sure what you are planning is suitable for you.

Using a fatigue diary

There are no medical tests to measure fatigue. Your specialist nurse may suggest using a numeric rating scale (NRS). For example, they may ask you to give your fatigue a score from 0 to 10, where 0 is no fatigue and 10 is the worst possible fatigue. Or you may be asked to rate your fatigue as none, mild, moderate or severe.

It is important that you tell your healthcare team how you feel and whether fatigue is affecting your day-to-day activities. You may find it useful to keep a daily diary to:

  • record your energy levels at different times of the day
  • find any patterns
  • find out if anything makes your fatigue better or worse
  • plan important activities for when you have more energy.

You could use our fatigue diary to do this. There is enough space to record your energy levels for 1 month. It explains a bit more about using a scale to describe your fatigue. It is a good idea to share your diary with your healthcare team. They can talk to you about how you can plan your day depending on how you feel.

We have some suggestions about things you can do to help manage your fatigue:

  • Physical activity

    If you have fatigue, you may become less active over time. When your muscles are not being used regularly, they become weaker. This is called deconditioning. There is good evidence that physical activity, such as walking quickly, is one of the best ways to help reduce symptoms of fatigue. Being active may also increase your appetite, give you more energy, improve sleep and help with mood.

  • Healthy diet and weight

    Eating well and keeping to a healthy weight can help you maintain or regain your strength. It can also give you more energy. It can help to keep a diary of what you eat and when to find out if you have more energy after certain meals. Drink plenty of fluids and try different foods or eat foods that taste best to you if you have taste changes. You can ask your doctor to refer you to a dietitian for helpful ideas.

  • Sleep

    Even though your fatigue may make you feel like sleeping all the time, try to keep to a normal sleep routine. Good quality sleep may help with fatigue, as well as reduce your need to sleep during the day. Talk to your cancer doctor, specialist nurse or GP if you are having trouble sleeping.

    You may be eligible for Sleepio. This is a personalised digital programme which features a step-by-step guide to help with poor sleep (insomnia).

  • Complementary therapies

    Complementary therapies include relaxation, mindfulness-based stress reduction (MBSR) and yoga. Before you use a complementary therapy, talk to your cancer doctor or specialist nurse. Some therapies may affect your cancer treatment. Some therapies may be available on the NHS or you may be able to get them through a cancer support group in your local area. If you find a complementary therapist, make sure that they are qualified and registered.


Booklets and resources

Living with fatigue

If you have fatigue, planning ahead can help. You could try planning your day so that you have energy to do the things that are most important to you. Pace yourself, take short naps and rests but try to balance them with some activity or exercise.

It is also important to plan around your treatment. Cancer treatment affects people in different ways. On days when you feel less well, it is okay to be less active and to rest more.

You could use our fatigue diary [PDF, 89KB] to keep a record. Write down the times when you feel your best and when you feel most tired. This may help you plan what time of day is best to do more tiring activities.

You may find some of the following suggestions helpful for managing everyday activities:

  • Housework

    • Spread tasks out over the week. Try to do a little bit each day rather than lots at one time.
    • If possible, ask other people to do hard work, such as hoovering, gardening or taking the rubbish out.
    • Sit down to do some tasks, if you can.
    • If possible, employ a cleaner to help. This may be expensive. Your local Age UK or the British Red Cross may be able to provide a home help service. You may have to pay for this.
    • Use long-handled dusters, mops and dustpans where possible to avoid stretching and bending.


  • Shopping

    • Make a list before you start, so you do not waste energy or time.
    • If possible, go grocery shopping with a friend or family member who can help.
    • Use a shopping trolley even if you are only buying a few things.
    • A wheeled shopping bag may be helpful when shopping and getting things home.
    • Most large supermarkets offer online shopping that can be delivered to your home, which you might find easier.


  • Preparing meals

    • Try having ready-made meals or pre-cooked food when you are most tired.
    • If you can, sit down while preparing meals.
    • Prepare extra meals or portions when you are feeling less tired and freeze them for when you feel too tired to cook.
    • Try not to lift heavy pans when serving. Instead, take your plate to the cooker and put your food on it there.


  • Washing and dressing

    • If you can, sit down in the bath rather than standing in a shower as this may save your energy.
    • If you have a shower, sit down if you can to avoid standing for too long. An occupational therapist (OT) may be able to provide equipment to help you in the shower.
    • Wear clothes that are easy to put on and take off.
    • Sit down when you are getting dressed.


  • Childcare

    • Explain to any children that you feel tired often and will not be able to do as much with them as before. You may be surprised at how well they respond.
    • Plan activities with them that you can do sitting down such as reading or doing a jigsaw puzzle.
    • Avoid carrying small children if you can. Use a pram or pushchair instead.
    • Accept help from family or friends, or ask for help. For example, someone may be able to take the children to and from school


  • Driving

    • Do not drive if you feel very tired.
    • If possible, ask a family member or friend to drive you.
    • If you need to get to hospital appointments, ask your nurse or doctor if there is any hospital transport available so that you do not have to drive.
    • If you do have to drive, plan your trip for when you usually feel more alert. Try to avoid driving at times when the roads are busiest.


Occupational therapists

Your cancer doctor, specialist nurse or GP can refer you to an occupational therapist.

Occupational therapists help people who have difficulty moving around or doing everyday tasks such as dressing, washing and cooking. They can help with practical ways to make a home safe, comfortable and easy to live in. They may be able to visit you at home to help you find ways to do things more easily.

Coping at work

Many employers can make changes to your workplace or working arrangements as part of reasonable adjustments.

Talk to your manager openly about ways to allow you to keep working or return to work. If you are self-employed, it can help to talk to the Department for Work and Pensions about benefits that you may be entitled to.

Getting support

Dealing with fatigue can affect your feelings. If you are finding it difficult to cope, it can help to talk to someone close to you, such as a family member or friend. Or you may prefer to talk to someone in your healthcare team.


If you feel anxious or depressed, you may find counselling helpful. Counsellors are trained to listen. They can help you deal with difficult emotions.

Many hospitals have counsellors or staff who are trained to provide emotional support to people affected by cancer. Your cancer doctor or specialist nurse can tell you what services are available. They can also refer you. Some GPs have counsellors in their practice, or they can refer you to one.

If you would like to find out more about counselling, our cancer support specialists can tell you more about services in your area. You may need to pay for counselling.

Support groups

It can help to talk to other people with fatigue. You could try talking to other people at the hospital, or join a local support group.

Most areas in the UK have cancer support groups. They are sometimes led by a healthcare professional. Some people find groups helpful, and make close relationships with other members. But if you try a group and it is not right for you, you do not have to go again.

Each group is unique. There are groups for people affected by a certain type or stage of cancer, or those who are having a particular treatment. There are a small number of groups for LGBTQ+ people affected by cancer.

Ask your healthcare team about groups in your area, or call us free on 0808 808 00 00. You can also search our database for groups in your area.

Online support

Many people get support on the internet. Online support groups for people affected by cancer include: social networking sites, forums, chat rooms and blogs.

You can use these to ask questions, get support and give advice yourself. Our Online Community is a social networking site where you can talk to people, write blogs and share your experience. There are many different groups including groups for specific cancer types, family members and friends, LGBTQ+ people and practical issues.

Caring for someone with fatigue

Caring for someone with fatigue may include helping with personal care, providing transport or organising appointments. If you are caring for someone with fatigue, there are things you can do to help:

  • Acknowledge that fatigue is difficult to cope with.
  • Use a fatigue diary to plan. This will help you both see when the person with fatigue has more or less energy to do things.
  • Try to help the person you care for be more active or make changes to their diet, to help them reduce their fatigue.

You can also go to appointments at the hospital with the person you care for. You could help them explain to their healthcare team how the fatigue is affecting them. It may help to show the team the person’s fatigue diary and ask their advice about what else you can do to help.

Looking after yourself

It is important to look after yourself when you are caring for someone else. Taking the time to focus on your own health and wellbeing will also benefit the person you look after.

You can ask the adult social services at your local council for an assessment of your needs, to see what might help you. This is called a carer’s assessment. It is important to talk about your own wellbeing.

We have more information about looking after yourself when caring for someone.

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About our information

  • Reviewers

    This information has been written, revised and edited by Macmillan Cancer Support’s Cancer Information Development team. It has been reviewed by expert medical and health professionals and people living with cancer. It has been approved by Chief Medical Editor, Professor Tim Iveson, Consultant Medical Oncologist.

    Our cancer information has been awarded the PIF TICK. Created by the Patient Information Forum, this quality mark shows we meet PIF’s 10 criteria for trustworthy health information.

The language we use

We want everyone affected by cancer to feel our information is written for them.

We want our information to be as clear as possible. To do this, we try to:

  • use plain English
  • explain medical words
  • use short sentences
  • use illustrations to explain text
  • structure the information clearly
  • make sure important points are clear.

We use gender-inclusive language and talk to our readers as ‘you’ so that everyone feels included. Where clinically necessary we use the terms ‘men’ and ‘women’ or ‘male’ and ‘female’. For example, we do so when talking about parts of the body or mentioning statistics or research about who is affected.

You can read more about how we produce our information here.

Date reviewed

Reviewed: 01 July 2023
Next review: 01 July 2027
Trusted Information Creator - Patient Information Forum
Trusted Information Creator - Patient Information Forum

Our cancer information meets the PIF TICK quality mark.

This means it is easy to use, up-to-date and based on the latest evidence. Learn more about how we produce our information.