Bronchitis is an infection of the main airways of the lungs (bronchi), causing them to become irritated and inflamed.
The main symptom is a cough, which may bring up yellow-grey mucus (phlegm). Bronchitis may also cause a sore throat and wheezing.
Read more about the symptoms of bronchitis.
When to see your GP
Most cases of bronchitis can be treated easily at home with rest, non-steroidal anti-inflammatory drugs (NSAIDs) and plenty of fluids.
You only need to see your GP if your symptoms are severe or unusual – for example, if:
- your cough is severe or lasts longer than three weeks
- you have a constant fever (a temperature of 38°C – 100.4°F – or above) for more than three days
- you cough up mucus streaked with blood
- you have an underlying heart or lung condition, such as asthma or heart failure
Your GP may need to rule out other lung infections, such as pneumonia, which has symptoms similar to those of bronchitis. If your GP thinks you may have pneumonia, you will probably need a chest X-ray, and a sample of mucus may be taken for testing.
If your GP thinks you might have an undiagnosed underlying condition, they may also suggest a pulmonary function test. You will be asked to take a deep breath and blow into a device called a spirometer, which measures the volume of air in your lungs. Decreased lung capacity can indicate an underlying health problem.
Treating bronchitis
In most cases, bronchitis will clear up by itself within a few weeks without the need for treatment. This type of bronchitis is known as "acute bronchitis". While you are waiting for it to pass, you should drink lots of fluid and get plenty of rest.
In some cases, the symptoms of bronchitis can last much longer. If symptoms last for at least three months, it is known as "chronic bronchitis". There is no cure for chronic bronchitis, but there are several medications to help relieve symptoms. It is also important to avoid smoking and smoky environments, as this can make your symptoms worse.
Read more about treating bronchitis.
Why do I have bronchitis?
The bronchi are the main airways in your lungs, which branch off on either side of your windpipe (trachea). They lead to smaller and smaller airways inside your lungs, known as bronchioles.
The walls of the bronchi produce mucus to trap dust and other particles that could otherwise cause irritation.
Most cases of acute bronchitis develop when an infection causes the bronchi to become irritated and inflamed, which causes them to produce more mucus than usual. Your body tries to shift this extra mucus through coughing.
Smoking is the most common cause of chronic bronchitis. Over time, tobacco smoke can cause permanent damage to the bronchi, causing them to become inflamed.
Read more about the causes of bronchitis.
Complications
Pneumonia is the most common complication of bronchitis. It happens when the infection spreads further into the lungs, causing air sacs inside the lungs to fill up with fluid. 1 in 20 cases of bronchitis leads to pneumonia.
People at an increased risk of developing pneumonia include:
- elderly people
- people who smoke
- people with other health conditions, such as heart, liver or kidney disease
- people with a weakened immune system
Mild pneumonia can usually be treated with antibiotics at home. More severe cases may require admission to hospital.
Read more about the treatment of pneumonia.
Who is affected
Acute bronchitis is one of the most common types of lung infection, and is one of the top five reasons for GP visits.
Acute bronchitis can affect people of all ages, but is most common in younger children under the age of five. It is more common in winter, and often develops following a cold, sore throat or flu.
It is estimated that there are around 2 million people in the UK affected by chronic bronchitis. Most of these are adults over the age of 50.
Chest infections are common, especially after a cold or flu during autumn and winter.
Although most are mild and get better on their own, some can be serious or even life-threatening.
This page covers:
Signs and symptoms of a chest infection
What causes chest infections?
Caring for your symptoms at home
When to see a doctor
Preventing chest infections
Signs and symptoms of a chest infection
The main symptoms of a chest infection can include:
- a persistent cough
- coughing up yellow or green phlegm (thick mucus), or coughing up blood
- breathlessness or rapid and shallow breathing
- wheezing
- a high temperature (fever)
- a rapid heartbeat
- chest pain or tightness
- feeling confused and disorientated
You may also experience more general symptoms of an infection, such as a headache, fatigue, sweating, loss of appetite, or joint and muscle pain.
What causes chest infections?
A chest infection is an infection of the lungs or airways. The main types of chest infection are bronchitis and pneumonia.
Most bronchitis cases are caused by viruses, whereas most pneumonia cases are due to bacteria.
These infections are usually spread when an infected person coughs or sneezes. This launches tiny droplets of fluid containing the virus or bacteria into the air, where they can be breathed in by others.
The infections can also be spread to others if you cough or sneeze onto your hand, an object or a surface, and someone else shakes your hand or touches those surfaces before touching their mouth or nose.
Certain groups of people have a higher risk of developing serious chest infections, such as:
- babies and very young children
- children with developmental problems
- people who are very overweight
- elderly people
- pregnant women
- people who smoke
- people with long-term health conditions, such as asthma, heart disease, diabetes, kidney disease, cystic fibrosis or chronic obstructive pulmonary disease (COPD)
- people with a weakened immune system – this could be due to a recent illness, a transplant, high-dose steroids, chemotherapy or a health condition, such as an undiagnosed HIV infection
Read more about the causes of bronchitis and the causes of pneumonia
Caring for your symptoms at home
Many chest infections aren't serious and get better within a few days or weeks. You won't usually need to see your GP, unless your symptoms suggest you have a more serious infection (see below).
While you recover at home, you can improve your symptoms by:
- getting plenty of rest
- drinking lots of fluid to prevent dehydration and to loosen the mucus in your lungs, making it easier to cough up
- treating headaches, fever and aches and pains with painkillers – such as paracetamol or ibuprofen
- drinking a warm drink of honey and lemon – to relieve a sore throat caused by persistent coughing
- raising your head up with extra pillows while you're sleeping – to make breathing easier
- using an air humidifier or inhaling steam from a bowl of hot water – to ease your cough (hot water shouldn't be used to treat young children with a cough, due to the risk of scalds)
- stopping smoking
Avoid cough medicines, as there's little evidence they work, and coughing actually helps you clear the infection more quickly by getting rid of the phlegm from your lungs.
Antibiotics aren't recommended for many chest infections, because they only work if the infection is caused by bacteria, rather than a virus.
Your GP will usually only prescribe antibiotics if they think you have pneumonia, or you're at risk of complications such as fluid building up around the lungs (pleurisy).
If there's a flu outbreak in your local area and you're at risk of serious infection, your GP may also prescribe antiviral medication.
Read more about treating bronchitis and treating pneumonia
When to see a doctor
You should see your GP if:
- you feel very unwell or your symptoms are severe
- your symptoms are not improving
- you feel confused, disorientated or drowsy
- you have chest pain or difficulty breathing
- you cough up blood or blood-stained phlegm
- your skin or lips develop a blue tinge (cyanosis)
- you're pregnant
- you're 65 or over
- you're very overweight and have difficulty breathing
- you think a child under five has a chest infection
- you have a weakened immune system
- you have a long-term health condition
- you have a cough that has lasted more than 3 weeks
Your GP should be able to diagnose you based on your symptoms and by listening to your chest using a stethoscope (a medical instrument used to listen to the heart and lungs).
In some cases, further tests – such as a chest X-ray, breathing tests and testing phlegm or blood samples – may be necessary.
Preventing chest infections
There are measures you can take to help reduce your risk of developing chest infections and stop them spreading to others.
Stop smoking
If you smoke, one of the best things you can do to prevent a chest infection is to stop. Smoking damages your lungs and weakens your defences against infection.
Read more information and advice about stopping smoking
Good hygiene
Although chest infections generally aren't as contagious as other common infections, like flu, you can pass them on to others through coughing and sneezing.
Therefore, it's important to cover your mouth when you cough or sneeze, and to wash your hands regularly. Put tissues in the bin immediately.
Alcohol and diet
Excessive and prolonged alcohol misuse can weaken your lungs' natural defences against infections and make you more vulnerable to chest infections.
To keep your risk of alcohol-related harm low, the NHS recommends:
- not regularly drinking more than 14 units of alcohol a week
- if you drink as much as 14 units a week, it's best to spread this evenly over three or more days
- if you're trying to reduce the amount of alcohol you drink, it's a good idea to have several alcohol-free days each week
Regular or frequent drinking means drinking alcohol most weeks. The risk to your health is increased by drinking any amount of alcohol on a regular basis.
Eating a healthy, balanced diet can help strengthen the immune system, making you less vulnerable to developing chest infections.
Read more about healthy eating and tips on cutting down on alcohol
Vaccinations
If you're at an increased risk of chest infections, your GP may recommend being vaccinated against flu and pneumococcal infections (a bacterium that can cause pneumonia).
These vaccinations should help to reduce your chances of getting chest infections in the future.
Flu and pneumococcal vaccinations are usually recommended for:
- babies and young children
- pregnant women (flu jab only)
- people aged 65 and over
- people with long-term health conditions or weakened immune systems