Pneumonia is swelling (inflammation) of the tissue in one or both of your lungs. If you experience any symptoms of pneumonia (see below), contact your GP, or the GP out of hours service if your GP surgery is closed.

About pneumonia

Pnuemonia is usually caused by an infection with a germ (bacteria or virus). At the end of the breathing tubes, in your lungs, there are clusters of tiny air sacs. If you have pneumonia, they become inflamed and fill up with fluid. Pneumonia can affect people of any age.

Symptoms of pneumonia 

The symptoms of pneumonia can develop suddenly (over 24-48 hours) or may come on more slowly, over several days.

Pneumonia symptoms vary and can be similar to those of other chest infections, such as acute bronchitis.

Common symptoms

You are likely to have a cough. This can be dry, or may produce thick mucus (phlegm) that is yellow, green, brownish or blood-stained.

Other common symptoms include:

  • difficulty breathing – your breathing may be rapid and shallow, and you may feel breathless, even when resting
  • rapid heartbeat
  • fever
  • feeling generally unwell
  • sweating and shivering
  • loss of appetite
  • pain in your chest – which gets worse when breathing or coughing

Less common symptoms

Less commonly, symptoms of pneumonia can include:

Pneumonia can affect people of any age, although it is more common and can be more serious in groups such as:

  • babies, young children and elderly people
  • people who smoke
  • people with other health conditions, such as a lung condition or a weakened immune system

Treating pneumonia 

Mild cases of pneumonia can usually be treated at home with antibiotics and plenty of rest and fluids. For people with other health conditions, pneumonia can sometimes be severe and may need to be treated in hospital.

When to seek medical help 

If you experience any symptoms of pneumonia (see above), contact your GP, or the GP out of hours service (OOH) if your GP surgery is closed.

If you are experiencing severe symptoms – particularly rapid breathing /shortness of breath, pain on breathing or confusion – you should call 999 for an ambulance immediately.

Causes of pneumonia

Pneumonia is most commonly caused by an infection, usually bacterial. However, there are several different bacteria that may cause it. Viruses and more rarely fungi may also cause pneumonia.

The germs that cause an infection are usually breathed in. In rare cases, pneumonia can develop from an infection elsewhere in your body, when germs enter your lungs through your bloodstream.

Preventing pneumonia 


The following lifestyle factors can increase your risk of developing pneumonia:

  • smoking
  • alcohol abuse
  • intravenous drug abuse

Smoking damages your lungs, which means they become infected more easily. If you smoke, the best thing you can do to prevent pneumonia is to quit smoking.

There is free specialist advice available to help you quit smoking. Stop smoking support services, through GP practices and community pharmacies, are available across Northern Ireland.


To help protect against more common infections causing pneumonia, people in higher risk groups should be vaccinated. The recommended vaccinations are:

  • the pneumonia jab (pneumococcal vaccination), which protects against pneumococcal infections
  • the flu jab

Good hygiene

You can help to stop germs spreading to other people by practising good hygiene. For example:

For example:

  • when you cough or sneeze, cover your mouth and nose with a tissue to catch the germs
  • throw used tissues away immediately, in a bin or toilet – germs can live for several hours after they leave your nose or mouth
  • wash your hands regularly, to avoid transferring germs to other people or objects


The information on this page has been adapted from original content from the NHS website.

For further information see terms and conditions.

This page was reviewed June 2018

This page is due for review September 2019

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