There are many causes of a cough in children, including infections (both viral and bacterial), irritations (cold air, smoke, inhaled foreign body), allergies, asthma and psychological causes (habit cough).
By far the most common cause of cough is a viral infection, with the cough usually occurring as part of a cold.
The next most common cause of coughing is asthma. Other causes of a cough are relatively uncommon.
The nature of your child’s cough and any associated symptoms will vary according to its cause.
A cough that follows a cold will be loose and sometimes produce mucus. Often it’s worse at night, because when your child lies down, mucus drips from the back of her nose and mouth into her wind pipe. The cough might persist for up to six weeks after the other symptoms of the cold have disappeared.
The cough associated with asthma is often worse at night or after exercise. Your child might also have an associated wheeze and breathing difficulties, such as shortness of breath.
A barking, hoarse cough could mean your child has croup.
The sudden onset of a cough with associated wheezing, following a choking episode, might suggest an inhaled foreign body.
If your child has had a very heavy cold, then gets bouts of coughing for many weeks, where he ‘barks’ when breathing out and makes a ‘whooping’ sound when breathing in, he might have whooping cough.
In a child less than 12 months old, a cough that’s associated with difficulty in breathing might be caused by bronchiolitis.
In an older or adolescent child, a cough might develop into a habit. Usually such coughs are ‘honking’ coughs and don’t happen when the child’s asleep.
When to see your doctor
Your child should see a doctor if:
- the cough goes on for longer than a week or two after a cold
- there’s a sudden onset of cough
- the cough is significantly interfering with your child’s sleep or daily life
- there’s any difficulty with breathing
- there’s an associated high fever
- your child’s skin changes colour, and turns blue or very pale.
In most cases, you don’t need to see a doctor if your child’s well except for his cough.
Most children with a cough don’t need any tests. A doctor will work out what the trouble is by taking a careful history of your child’s cough and any other symptoms, and also by physically examining your child.
The doctor might order a chest X-ray if your child has had pneumonia or to make sure your child hasn’t inhaled something. A blood test might be helpful in working out whether there’s a serious infection present.
If your child’s cough is caused by asthma, it’s treated with medications, depending on the nature and extent of the symptoms and the age of your child. You can read more about treating asthma.
The most common cough is the one that follows a cold, and it doesn’t need any specific treatment. In this case, most children don’t need antibiotics, because the original infection was caused by a virus and antibiotics only treat bacteria. This cough is likely to be caused by prolonged irritation of the respiratory tract, rather than an ongoing infection.
Cough medicines and expectorants (medicines that are supposed to help cough up mucus from the lungs and airways) haven’t been shown to make any difference to a cough.
Vaporisers and humidifiers similarly haven’t been shown to relieve coughing. There are dangers in young children accidentally swallowing the vaporiser solution (usually containing menthol or eucalyptus) or burning themselves.
Honey might reduce the severity and duration of a cough. Note that honey shouldn’t be given to children under one because of the risk of infantile botulism (a rare but serious form of food poisoning).
Usually a cough following a cold will improve with the passage of time, no matter how you treat it.
If your child’s cough is caused by asthma, you can usually prevent it with appropriate treatment.
You can minimise the risk of inhaling foreign bodies by not letting toddlers and infants eat nuts or play with small objects that can be easily inhaled.
Unfortunately, you can’t prevent the cough caused by a viral infection.