Causes of chronic cough in children and how to treat it

All children experience acute coughs as they grow up as they catch colds and other viral infections. As a child’s immune system doesn’t fully mature until around age 12 to 14 years, viral infections are more common in young children, occurring on average eight to 10 times a year. Unlike an acute cough, chronic (long-term) cough refers to a dry or wet cough that persists for more than four weeks. 

Sometimes a series of acute coughs can be mistaken for chronic cough. Close inspection of the history of symptoms is important to identify whether coughing occurs persistently over weeks or if instead occurs during intermittent bouts. 

Common causes of chronic cough

Conditions that cause an acute cough can, in some cases, eventually cause chronic cough. This includes viral infections, tonsillitis, pneumonia, foreign bodies in your respiratory system, whooping cough, croup and bronchiolitis. However, the most common cause of chronic cough is asthma. 

Other causes of chronic cough include tuberculosis, bronchiectasis, cystic fibrosis, primary ciliary dyskinesia (PCD), structural problems with the windpipe (trachea), exposure to allergens (eg house dust mites) and exposure to toxins (eg tobacco smoke).

If you have allergic rhinitis (eg hayfever), you can develop a post-nasal drip, where mucus from your nose or sinuses drips into the back of your throat. This can lead to a chronic cough. 

If you have gastro-oesophageal reflux disease (GORD), where the fluid contents of your stomach leak upwards into your gullet (oesophagus), especially when lying down, you can also develop a chronic cough. 

In the last 15 years, bacterial bronchitis has been identified as a cause of chronic cough. This develops when the airways become inflamed (eg due to a viral infection) and so produce more mucus, which results in a wet cough. As children often cannot cough up this mucus, trapped mucus can become infected with bacteria, resulting in bacterial bronchitis. 

This may be associated with a floppy windpipe, which is assessed via a procedure called flexible fibreoptic bronchoscopy, where a thin, stethoscope-like, bendy tube with a camera and a light on the end (a bronchoscope) is passed into your child’s airways via their mouth. In children, this is always performed under general anaesthetic. 

If your child has a wet cough for two weeks or more, see your GP as soon as possible as left untreated, bacterial bronchitis can cause permanent lung damage. 

How to spot the signs of a chronic cough

Viral infections that cause acute coughs are often accompanied by a fever and runny nose, which can lead to poor sleep and even vomiting. The respiratory symptoms are usually restricted to the upper airways ie nose and throat. 

In contrast, a chronic cough causes symptoms in the lower airways, such as wheezing, whistling, rattling, and/or croupy noises when breathing, and rapid, laboured breathing. You can tell if your child’s breathing is laboured as the movement of their chest will be more pronounced and they may make a sucking sound when breathing in. 

These lower airway symptoms can also cause your child to feel very tired, lose their appetite and become dehydrated. 

If you notice any lower airway symptoms, see your GP. 

It is important to be aware that in some children, the signs of chronic cough can be subtle ie they may still have lots of energy. It is still important to see your GP to avoid the potential risk of permanent damage to their airways caused by certain types of chronic cough. 

Diagnosing chronic cough

If you're worried your child has a chronic cough, see your GP. They will ask you questions about their medical history, symptoms and life events eg have they recently joined a nursery. 

They will also ask about your family medical history and lifestyle eg if there is anyone in your family with a chronic cough, asthma, cystic fibrosis, primary ciliary dyskinesia (PCD) or allergies, or if anyone recently returned from travel abroad to a country where there are high rates of tuberculosis.

Your GP will also listen to their chest using a stethoscope. Depending on the results of their examination, they may refer your child for further tests, such as blood tests or a chest X-ray. In cases where all tests are negative and/or any previous treatment hasn’t been successful, your child may need to have a flexible bronchoscopy. This allows the doctor to examine the inside of their airways and collect a sample of mucus. 

Treating a chronic cough

If your child’s acute cough is caused by a virus, in most cases, no treatment is needed — antibiotics are not effective against viruses. 

If it is suspected that your child has bacterial bronchitis, they will be prescribed a long course of antibiotics (ie two to eight weeks). As the reach of antibiotics into the airways is not good, a short course of antibiotics is not usually enough to resolve the infection. 

If an allergy may be the cause of your child’s chronic cough, allergy testing may be arranged and your doctor may prescribe antihistamines. 

If your child’s chronic cough is caused by asthma, they will be given a reliever inhaler with a spacer device and may also need steroids to help reduce the inflammation of their airways. 

Risks of chronic cough

Depending on the underlying cause, chronic cough can lead to lung scarring, bronchiectasis and ultimately reduced lung function.

Normally, lung function increases through childhood until it reaches its peak in adulthood. If your child’s lung function is impaired due to a chronic cough, it may not reach its full potential. The subsequent decline in lung function that we all experience with ageing will, consequently, be more rapid when they are older.

Untreated chronic cough in childhood can, therefore, have lifelong consequences.