Cancer and its treatments may cause breathlessness. There are different ways to help manage breathlessness.

Causes of breathlessness

If you are breathless, you may experience uncomfortable or fast breathing. You may feel short of breath or your chest may feel tight.

There are different causes of breathlessness. Your doctor can explain the cause of your breathlessness and help you find the best treatment.

  • If your breathlessness gets worse quickly or you have pain when you breathe, contact your doctor immediately as you may need urgent treatment.
  • If you cannot speak to your doctor and your breathlessness continues to get worse, go straight to your nearest A&E (emergency department).

Different causes of breathlessness include:

  • Cancer affecting the lungs

    This can be a primary lung cancer that started in the lungs. Or it may be a secondary cancer that has spread to the lungs from another part of the body.

  • A build-up of fluid in the lining of the lungs (pleural effusion) or abdomen (ascites)

    If cancer cells irritate the lining of the lungs or tummy area (abdomen), this can cause a build-up of fluid. This means there is less room for the lungs to expand. Pleural effusion or ascites can be treated by draining the fluid.

  • Low levels of red blood cells (anaemia)

    Red blood cells carry oxygen around the body. If the level of red blood cells in your blood is low, you may become very tired and breathless. Your doctors may recommend that you have a blood transfusion.

  • Chest infections

    These cause phlegm in the airways and can make you feel breathless. If you develop a high temperature (above 37.5°C (99.5F), a chesty cough or pain when you breathe, contact your doctor immediately. You may need antibiotic treatment.

  • Weakened muscles

    In advanced cancer, the muscles that help breathing can become weak because of fatigue, lack of nutrition, weight loss and reduced physical activity. This can make breathing more difficult.

  • Pain

    Pain can make it hard to breathe and move comfortably. Tell your doctor if you have any pain. They can make sure it is well controlled. There are different types of painkiller that can help.

  • A blood clot in the lung (pulmonary embolism)

    This can cause sudden breathlessness and pain when you breathe. If you have these symptoms, contact your doctor immediately.

  • Other conditions

    Some other conditions can cause breathlessness, such as fluid in the lungs. Your doctor can advise you about the treatment you need.

  • Smoking

    Smoking makes breathlessness worse. The smoke irritates and inflames the airways. This means less oxygen is absorbed into the bloodstream. If you want to stop smoking, ask your nurse or doctor about help that is available locally.

  • Cancer treatments

    Surgery for lung cancer, radiotherapy to the chest and some anti cancer drugs can sometimes cause breathing problems. Your cancer specialist can tell you about any effects your treatment may have on your breathing, and answer any questions you have.

  • Feelings of anxiety and panic

    Anxiety and panic can cause some people to have rapid and shallow breathing.

Managing and treating breathlessness

If you have breathlessness, there are ways to manage it and treatments that may help. These may include:

  • breathing exercises and relaxation techniques (controlled breathing)
  • using a handheld fan
  • medicines
  • oxygen treatment.

Who can help

Many people are available to help you and your family and friends manage the problems that breathlessness can cause. These include:

  • your GP
  • clinical nurse specialist
  • physiotherapist occupational therapist (OT)
  • dietitian
  • palliative care nurses (sometimes called Macmillan nurses).

Your doctor may suggest using a Borg scale to show how breathless you feel at different times. A Borg scale uses numbers 0 to 10, with 10 being severe breathlessness. You can use this to keep a diary of your breathlessness.

Download PDF: Borg scale


Making a plan for when you are breathless

You may find it helpful to write a plan for when you feel breathless. This could be a resting position that you know helps, having the fan turned on or the window opened. Having a plan will also help your carers support you when you are breathless.

Managing everyday activities

There are things you can do to manage breathlessness if it is having an effect on your day to day life. You may find it helpful to:

  • prioritise things you most enjoy or things that need doing most
  • plan ahead
  • arrange your home to make daily tasks easier
  • sit down to wash, dress or prepare food.

Do not be afraid to ask for help from family and friends. If you live alone and are struggling, talk to your doctor about what help is available.

You can ask to see a physiotherapist or an occupational therapist (OT) for some expert help.

Your feelings about breathlessness

Your feelings may change at different times during your illness. Some days you may feel frightened, stressed, angry, sad and even guilty.

These are normal responses to breathlessness, the cancer, the treatment and any fears you have about the future. There’s no right or wrong way to deal with these feelings, but accepting they are normal will help.

Sometimes you may feel you need to be alone. Other times you may want to be with people. Do what feels right for you at the time.

You may have family and friends who find your changing emotions hard to understand. But try talking together about how you all feel. This can help you understand each other better and be able to cope with the problems more easily. You can also talk to your doctor or nurse for support.

Booklets and resources

Date reviewed

Reviewed: 01 March 2019
Next review: 01 March 2022

This content is currently being reviewed. New information will be coming soon.

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