Bronchitis vs pneumonia: how the two chest infections differ

Bronchitis and pneumonia are both infections of the chest that usually begin with a cough, and the early days can feel very alike. The main difference is how deep and how serious the problem is. The NHS describes bronchitis as inflammation of the airways in the lungs that is usually caused by an infection and often gets better without treatment in around 3 weeks. It describes pneumonia as inflammation of the lungs, usually caused by an infection, that some people will need antibiotics for and that can make babies, older people and those with heart or lung conditions seriously ill.

In everyday terms, bronchitis is the milder of the two for most healthy adults, and pneumonia is the one that is more likely to need a doctor, a chest X-ray or a stay in hospital. That does not mean every case of bronchitis is trivial or every case of pneumonia is dangerous. A person with a long-term lung condition may become quite unwell with what looks like a simple chest cold, so the person and the context matter as much as the label.

Bronchitis affects the airways, the tubes that carry air into and out of the lungs. The NHS says it is usually caused by an infection and is often spread through coughing and sneezing. It also notes that some people have long-term inflammation of the airways, called chronic bronchitis, and that this is known as chronic obstructive pulmonary disease (COPD). That is a separate, long-term condition from the short-lived infection most people mean when they say bronchitis.

Pneumonia affects the lungs. The NHS says it is usually caused by a bacterial or viral infection and can sometimes follow another infection such as flu, respiratory syncytial virus (RSV) or COVID-19. Less commonly it can be caused by a fungal infection, which the NHS says is rare in healthy people in the UK, or by something getting into the lungs, such as water or food, which is called aspiration pneumonia. Asthma + Lung UK describes pneumonia as a type of chest infection.

The two lists overlap heavily, which is why people struggle to tell them apart at home. The table uses only what the NHS pages list for each condition.

There is no single symptom that separates the two. A clinician takes into account how unwell you are, how breathless you are, whether you have a long-term condition, your age and how the illness has developed. The pneumonia page notes that in hospital people may be sent for a chest X-ray and blood tests to check for other conditions, and that this is in addition to treatment with antibiotics and sometimes steroids and oxygen. The NHS bronchitis page does not describe a specific test for ordinary bronchitis, and says it usually gets better on its own.

The NHS advice on when to ask for help is also a useful guide to how the two are treated differently. For bronchitis it lists a cough of more than 3 weeks that is not improving, coughing up blood, being over 65 or pregnant, having a long-term condition such as diabetes or a heart, lung or kidney condition, having a weakened immune system, feeling too unwell for usual activities and feeling short of breath. For pneumonia it lists a cough of up to 3 weeks, yellow or green mucus, chest pain that comes and goes or happens on breathing or coughing, and shortness of breath. Because the lists overlap, you do not need to decide which one you have before asking for advice.

For bronchitis the NHS suggests resting, drinking plenty of fluids, taking paracetamol or ibuprofen for pain and a high temperature, adding honey to a warm drink to soothe the throat (not for babies under 1) and not smoking. It says antibiotics may be offered if the bronchitis is caused by a more serious infection, and that a GP should see you if symptoms last longer than 3 weeks.

For pneumonia, the NHS says bacterial pneumonia is usually treated with antibiotics and that most people get better in 2 to 4 weeks. Home treatment can include rest, plenty of fluids and paracetamol or ibuprofen if you have been told you can take it. It says not to take cough medicine, because coughing helps the body clear the infection. If you are given antibiotics at home you should finish the course even if you feel better, and contact your doctor if you do not feel any better after 2 to 3 days of taking them.

The NHS lists who may need hospital treatment for pneumonia: people over 65, people with cardiovascular disease or a long-term lung condition, babies and young children, people who are very unwell and people who are not getting better after taking antibiotics. In hospital you will usually be given antibiotics, sometimes steroids and sometimes oxygen.

Both NHS pages describe three levels of response. Call 999 or go to A&E if you are struggling to breathe, if your lips, skin or tongue are turning pale, blue or blotchy or grey, if you are coughing up blood (listed in the pneumonia advice), if you suddenly feel confused, or if you cannot wake a baby or they feel floppy. The NHS asks that you do not drive yourself to A&E.

Ask for an urgent GP appointment or call NHS 111 for the situations listed above, such as a cough that is not improving after 3 weeks, chest pain that comes and goes or shortness of breath, and for anyone with a health issue that makes them more vulnerable. Call 111 for advice if a child aged 4 or under seems unwell. If you are unsure which category you fall into, the safer choice is to ask.

The NHS lists vaccines that help protect against infections that can cause pneumonia. The pneumococcal vaccine is recommended for babies, adults over 65 and people at higher risk of pneumococcal infections. The flu vaccine is recommended in pregnancy, for adults over 65, people with certain long-term conditions and those at high risk of catching or passing on flu. The NHS also lists an RSV vaccine for adults aged 75 and over and for some other groups, and a seasonal COVID-19 vaccine for people at increased risk. Stopping smoking also reduces your chance of getting pneumonia. Asking your GP practice which of these apply to you is a practical next step.