A cough is a reflex action to clear your airways of mucus and irritants such as dust or smoke. It is rarely a sign of anything serious.
A “dry cough” means it is tickly and does not produce any phlegm (thick mucus). A “chesty cough” means phlegm is produced to help clear your airways.
Most coughs clear up within three weeks and don’t require any treatment. For more persistent coughs, it is a good idea to see a medical doctor so they can investigate the cause and prescribe a course of treatment.
A persistent cough may be caused by:
- A long-term respiratory tract infection, such as chronic bronchitis.
- Asthma – this also usually causes other symptoms, such as wheezing, chest tightness and shortness of breath.
- An allergy.
- Smoking – a smoker’s cough can also be a symptom of COPD
- Bronchiectasis – where the airways of the lungs become abnormally widened
- Postnasal drip – mucus dripping down the throat from the back of the nose, caused by a condition such as rhinitis or sinusitis.
- Gastro-Esophageal Reflux Disease [GERD] – where the throat becomes irritated by leaking stomach acid into the throat [oesophagus].
- A prescribed medicine, such as an angiotensin-converting enzyme inhibitor [ACE].
Rarely, a persistent cough can be a symptom of a more serious condition, such as lung cancer, heart failure, a pulmonary embolism (blood clot on the lung) or tuberculosis.
Coughs in children
Coughs in children often have similar causes to those mentioned above. For example, respiratory tract infections, asthma and GERD can all affect children.
Causes of coughs that are more common in children than adults include:
- Bronchiolitis – a mild respiratory tract infection that usually causes cold-like symptoms.
- Croup – this causes a distinctive barking cough and a harsh sound known as stridor when the child breathes in.
- Whooping cough – look out for symptoms such as intense, hacking bouts of coughing, vomiting, and a whooping sound with each sharp intake of breath after coughing
Occasionally, a persistent cough in a child can be a sign of a serious long-term condition, such as cystic fibrosis.
When to see a doctor
Seeking medical advice is necessary if the person experiences the following: a cough for more than three weeks, the cough is particularly severe or is getting worse, the person coughs up blood or experience shortness of breath, breathing difficulties or chest pain, presence of any other worrying symptoms, such as unexplained weight loss, a persistent change in the person’s voice, or lumps or swellings in the neck.
If the doctor is unsure what the cause of the cough is, they may refer to a hospital specialist for an assessment. They may also request some tests, such as a chest X-ray, allergy tests, breathing tests, and an analysis of a sample of the patient’s phlegm [mucus] to check for infection.
What treatments are available?
Treatment is not always necessary for mild, short-term coughs because it is likely to be a viral infection that will get better on its own within a few weeks. The person can look after themselves at home by resting, drinking plenty of fluids, and taking analgesics and painkillers.
Cough medicines and remedies
Although, some people find the use of cough remedies helpful. Medicines that claim to suppress the cough or stop the bringing up phlegm are not usually recommended. This is because there is little evidence to suggest they are any more effective than simple home remedies, and they are not suitable for everyone.
Treating the underlying cause
If a cough has a specific cause, treating this may help.
Asthma can be treated with inhaled steroids to reduce inflammation in the airways. Allergies can be treated by avoiding things the person is allergic to and taking antihistamines to dampen down the allergic reactions. Bacterial infections can be treated with antibiotics. GERD can be treated with antacids to neutralise the stomach acid and medication to reduce the amount of acid the stomach produces. COPD can be treated with bronchodilators to widen the airways. For smokers, quitting smoking is also likely to help improve cough.