Skip to main content

Breathlessness and difficulty breathing


Breathlessness is an unpleasant sensation of uncomfortable, rapid or difficult breathing. People say they feel puffed, short of breath or winded. The medical term is dyspnoea. Your chest may feel tight and breathing may hurt.

Everyone can experience breathlessness if they run for a bus or exert themself to an unusual extent. But it is important to seek medical attention if you experience breathlessness, as it may be due to a serious underlying problem.

The most common causes are discussed below.

Continue reading below

What is breathlessness?

Breathlessness is also called shortness of breath and difficulty in breathing. People with breathlessness might describe it as:

  • Feeling out of breath.

  • Feeling like the chest is very tight.

  • Feeling like they're not getting enough air in ('air hunger').

It's normal to feel breathless when doing heavy physical activity, like running. However, feeling breathless when resting, or doing very gentle physical activity (such as walking around the house) isn't normal, and can be a sign of a medical problem.

The medical term for breathlessness is dyspnoea.

Breathlessness may come on suddenly (acute) or gradually over a period of time (chronic).

The feeling of breathlessness happens when the brain detects that the body is not breathing hard or fast enough for its needs. The brain can detect this in several different ways: for example, it might detect that blood oxygen levels are too low, that blood carbon dioxide levels are too high, or that the blood is too acidic. So, the brain produces a feeling of breathlessness, and makes breathing harder and faster, trying to increase the amount of air coming into and out of the lungs to meet the body's needs.

Patient picks for Breathing difficulties

Who is affected by breathlessness?

Sudden severe breathlessness is one of the most common reasons that people call an ambulance or go to accident and emergency departments.

Everyone feels breathless when doing heavy exercise; what counts as heavy exercise depends on our fitness levels. Breathlessness that happens at rest or with light activity (for example, a gentle walk), or breathlessness that happens suddenly or unexpectedly can be due to a serious underlying medical condition.

Breathlessness can affect anyone. Pneumonia can affect the very young and the very old, asthma tends to affect young children, smokers are at greater risk of lung and heart disease and the elderly may develop heart failure. However, all these conditions can affect any age group and severe breathlessness always needs medical attention.

Continue reading below

How do you measure breathlessness?

There are various different ways for healthcare professionals to measure the severity of breathlessness. A commonly-used way is the Medical Research Council scale, which goes from one to five:

  1. No breathlessness, except during strenuous exercise (this is normal).

  2. Feeling breathless when hurrying on the flat, or feeling breathless when walking up a slight hill.

  3. Feeling breathless when walking at normal pace on the flat; walking slower than most people on the flat due to breathlessness; having to stop after a mile or so, or after about 15 minutes, due to breathlessness.

  4. Having to stop after walking about 100 yards (about 90 metres), or after a few minutes on level ground, due to breathlessness.

  5. Feeling too breathless to leave the house, or feeling breathless whilst dressing.

Another way is the Borg scale, which asks people to rate their shortness of breath on a scale from zero to ten.

More general ways to measure breathlessness, which healthcare professionals sometimes ask about, include:

  • Describing how far someone can walk before they have to stop for breath (exercise tolerance).

  • Describing activities that make someone feel breathless (such as running, walking, doing housework, or dressing).

What being breathless could mean

What investigations will be advised?

When seeing a healthcare professional about breathlessness, they will ask questions to try to work out what could be happening. These might include:

  • Did it start suddenly or develop over time? Did anything trigger it?

  • How far can you walk? Are you only breathless when you move? Is it worse when you lie down?

  • Do you feel ill? Do you have a high temperature (fever), weight loss or a cough? Do you have any pain in your chest?

  • Are you coughing up any phlegm (sputum)? What colour is it?

  • Have you lost weight, coughed up blood, been in contact with anyone with tuberculosis (TB) or travelled abroad recently?

  • Have you recently been bed-bound or on a long flight?

  • Do you smoke, and have you ever smoked?

They will usually ask to examine you. This is often an examination of the heart and lungs, but sometimes other areas as well. This is very helpful in working out the cause of breathlessness.

There are many different possible tests (investigations). Which ones are useful depends entirely on what your healthcare professional has learned from listening to you and examining you.

So, tests will differ from person to person and there is no 'standard' set of tests for breathlessness. Some people don't need any tests. Tests that might be used include:

Continue reading below

Diagnosing breathlessness

There are lots of different causes of breathlessness. Your doctor should use the information gained from listening to you, examining you, and any tests they have requested to try to determine the cause of the breathlessness. Sometimes, this is straightforward. Other times, it can be difficult, and sometimes a referral to someone who specialises in breathlessness is needed.

What causes breathlessness?

Many different things can cause breathlessness. Common causes are listed below.

Short-term/recent (acute) breathlessness
This means breathlessness that has come on over minutes, hours, or days. This may be caused by:

  • Asthma - you may sound wheezy and breathless. May be triggered by a cold (viral infection) or allergy (for example, hay fever).

  • Pneumonia - a severe chest infection in which you become more breathless. You feel ill, have a high temperature (fever) and cough with greenish phlegm (sputum).

  • COVID-19 - may cause breathlessness that develops over a few days.

  • A flare-up of chronic obstructive pulmonary disease (COPD) - a long-term lung condition causing breathlessness and cough. The airways become inflamed and narrowed. It may become suddenly worse as a result of a chest infection.

  • A flare-up of heart disease - for example, heart failure where the heart doesn't pump properly. Because the heart pumps inefficiently in heart failure, there is a build-up of pressure in blood vessels which feed into the heart (veins). This increased pressure makes fluid build up in the body's tissues. Because of gravity, the extra fluid shows up as ankle swelling.

  • Pulmonary embolism - a clot in the lung. Usually due to a blood clot in the leg, which causes a painful, swollen calf. The clot develops after being immobile for a long time (for example, after a long-haul flight) and travels in the bloodstream to the lungs.

  • Anxiety - can cause breathlessness, feelings of panic, rapid heartbeat (palpitations) and sweating.

  • Some medicines may cause breathlessness, especially if you already have a condition that causes breathlessness. For example, taking a beta-blocker (such as propranolol) or aspirin may cause breathlessness (if you have asthma).

  • Other causes - including pain, and anaemia - can cause breathlessness.

Long-term (chronic) breathlessness
This is breathlessness that has been there for weeks, months, or years. It has usually developed and worsened slowly. Common causes include:

  • Obesity and lack of fitness.

  • Asthma - which is not well controlled.

  • COPD - lung disease usually due to smoking.

  • Heart failure - gradual onset of breathlessness and swollen ankles - worse on lying down. It affects elderly people usually. It is due to the heart pumping inefficiently.

  • Heart rhythm problems - for example, an irregular heartbeat (atrial fibrillation) may make the heart work less well so oxygen isn't pumped around the body properly. This means you have to breathe rapidly to get more oxygen into your lungs. The rapid breathing makes you feel breathless.

  • Anaemia - not enough haemoglobin in the blood to carry oxygen to cells. This causes tiredness and breathlessness. The most common cause in the UK is heavy menstrual periods. Bleeding into the gut is a common cause in older people.

How to treat breathlessness

Treatment depends on the cause of the breathlessness. You will be strongly encouraged to stop smoking if you are a smoker. It will also help if you lose weight if you are overweight.

If required, you may be referred to a heart specialist (a cardiologist) or to a lung (respiratory) specialist, for further tests, depending on the most likely underlying cause. Most cases will be managed by your GP but you may be referred for further investigation and treatment at a hospital.

What can you do if you feel very breathless?

  • Try to keep calm.

  • Call 999/112/911 if severe and sudden with no obvious cause.

  • Call your GP urgently otherwise.

  • Use your reliever inhaler as instructed if you have asthma.

  • Use your oxygen if you have been supplied with it.

What can you do to help ongoing (chronic) breathlessness?

There are some breathing control techniques that can help to reduce breathlessness. Examples include:

  • Relaxed, slow, deep breathing: breathe in gently through your nose and breathe out through your nose and mouth. Try to stay feeling relaxed and calm.

  • Paced breathing: this may help when you are walking or climbing stairs. Try to breathe in rhythm with your steps at a speed you find comfortable.

  • Controlled breathing. This involves using your diaphragm and lower chest muscles to breathe instead of your upper chest and shoulder muscles. Breathe gently and keep your shoulders and upper chest muscles relaxed.

Use different comfortable seating and standing positions when you feel breathless. Different positions suit different people but examples include:

  • When standing up, lean from the hips with your forearms resting on something at a comfortable height, such as a chair or kitchen work surface.

  • When standing or walking, put your hands on your hips or in your pockets.

  • When sitting, lean forwards, resting your forearms on your knees, on the arms of a chair, or on a table.

Arrange the things you use every day to make sure they are easy to reach. Try to stay active but take a rest when you feel breathless and then start again.

Many people find that having a draft of air helps the sensation of breathlessness. You can do this by:

  • Opening a window.

  • Using a standing or desk fan to blow air towards you.

  • Using a hand-held fan to blow air onto your face.

It's thought that cooling the face with a fan sends messages to the brain to reduce the feelings of breathlessness.

Medications for breathlessness

Medicines can treat the underlying cause of the breathlessness, improving the symptoms. For example, inhalers can treat asthma and COPD, meaning people with asthma or COPD flare-ups feel less breathless. However, medicines have to be carefully matched to the cause of the breathlessness; an inhaler won't improve breathlessness caused by pneumonia, for example - so, medications used differ depending on the cause.

Breathlessness is a common symptom in end-of-life care. In people who are dying, it is often difficult or impossible to treat or reverse the underlying cause of their breathlessness. In this situation, medicines might be used to treat symptoms of breathlessness and relieve distress, such as:

  • Opioids - morphine and morphine-like drugs.

  • Benzodiazepines.

  • Oxygen - but only for people who have breathlessness due to low blood oxygen levels. It isn't helpful for everyone.

These medicines have side-effects and harms, particularly with long-term use, which is why they're usually only used in end-of-life care. For people who are dying, they can be really effective ways of reducing distressing breathlessness.

How can I avoid breathlessness?

You will need to find the underlying cause and try to address it if possible. Don't smoke, or if you do smoke, get help to stop smoking because all common serious causes of breathlessness are more likely to affect smokers. If you maintain a normal weight and do regular exercise, you are less likely to get breathless.

What is the outlook (prognosis)?

This depends on the underlying cause but is generally very good. People with smoking-related diseases who continue to smoke, tend to become more and more breathless. Some people who are breathless will need oxygen.

Further reading and references

  • Wahls SA; Causes and evaluation of chronic dyspnea. Am Fam Physician. 2012 Jul 15;86(2):173-82.
  • Ambrosino N, Fracchia C; Strategies to relieve dyspnoea in patients with advanced chronic respiratory diseases. A narrative review. Pulmonology. 2019 Sep - Oct;25(5):289-298. doi: 10.1016/j.pulmoe.2019.04.002. Epub 2019 May 22.
  • Palliative care - dyspnoea; NICE CKS, July 2022 (UK access only).
  • Breathlessness; NICE CKS, February 2022 (UK access only)

Article history

The information on this page is written and peer reviewed by qualified clinicians.

symptom checker

Feeling unwell?

Assess your symptoms online for free