Quick answer
What is chest infection?
A chest infection is an infection of the lungs or large airways, usually caused by a virus or sometimes bacteria. Symptoms include cough, breathlessness, chest discomfort and sometimes a high temperature. Many viral chest infections clear up within a few weeks, but see a GP if you feel very unwell, breathless, or symptoms last more than 3 weeks.
What is a chest infection?
A chest infection is an infection that affects the lungs or the large airways leading to them. It usually follows a cold or flu and is most common in autumn and winter. Most chest infections are mild and caused by viruses, but some — particularly pneumonia — can be more serious and need prompt treatment.
Symptoms
Common symptoms include:
- a cough — often bringing up phlegm (mucus)
- breathlessness or wheezing
- chest discomfort or tightness
- a high temperature, sweats and shivers
- feeling generally unwell, tired or achy
- headache
Symptoms may develop over a few days after a cold. How unwell you feel is often a better guide than the colour of your phlegm.
Bronchitis vs pneumonia
Bronchitis inflames the large airways. It usually causes a persistent cough with phlegm and often follows a viral cold. Most cases improve within two to three weeks.
Pneumonia affects the small air sacs in the lungs. It can cause more pronounced breathlessness, chest pain when breathing or coughing, and a higher fever. Pneumonia may need antibiotics and closer monitoring — a GP can assess this.
Treatment at home
For a mild viral chest infection:
- Rest — give your body time to recover.
- Fluids — stay well hydrated, especially with a fever.
- Paracetamol or ibuprofen — for aches and temperature, if suitable for you.
- Avoid smoke — smoking slows recovery and increases risk of complications.
Antibiotics are not usually needed for viral infections. A GP may prescribe them if they suspect bacterial pneumonia or another bacterial cause.
Who is at higher risk
Chest infections can be more serious in:
- babies and very young children
- adults aged 65 and over
- people with COPD, asthma or other lung conditions
- smokers
- people with weakened immune systems
- pregnant women
If you are in a higher-risk group, seek advice early rather than waiting.
When to see a GP
See a GP if you feel significantly unwell, are breathless on minimal exertion, have chest pain, a cough lasting more than three weeks, or are coughing up blood. Seek emergency help for severe breathlessness, confusion, or blue lips or skin.
Preventing chest infections
Good hand hygiene, flu vaccination if eligible, and not smoking all reduce risk. Treating underlying lung conditions well — for example, using asthma inhalers as prescribed — also helps.
Common questions
- What is the difference between bronchitis and pneumonia?
- Bronchitis mainly affects the large airways (bronchi) and usually causes a cough with phlegm. Pneumonia affects the small air sacs in the lungs and can make you more unwell, with higher fever, breathlessness and chest pain. A GP can assess which you have.
- Do I need antibiotics for a chest infection?
- Most chest infections are caused by viruses, so antibiotics will not help. Antibiotics may be needed if a GP thinks bacteria are involved — for example in some cases of pneumonia — but this is a clinical decision, not based on phlegm colour alone.
- How long does a chest infection last?
- Many people improve within two to three weeks. A cough can linger after other symptoms have settled. See a GP if you are not improving, or if a cough lasts more than three weeks.
- How can I recover at home?
- Rest, drink plenty of fluids, and take paracetamol or ibuprofen for fever and aches if suitable for you. Avoid smoking and smoky environments. A pharmacist can advise on cough remedies, though evidence for them is limited.
- When is a chest infection an emergency?
- Call 999 if you have severe difficulty breathing, sudden chest pain, confusion, or lips or skin turning blue. These can be signs of serious pneumonia or another emergency.