Cough

A cough is a protective reflex that clears mucus, dust, smoke, germs, and other material from the airways.

Coughing is a symptom, not a disease. A brief cough is often caused by a cold or another respiratory infection. A cough that continues or returns can have many causes, including asthma, nasal drainage, medicines, or smoke exposure.

An acute cough lasts less than three weeks. A cough lasting three to eight weeks is sometimes called subacute, while one lasting more than eight weeks is considered chronic in adults. Duration helps guide assessment but does not identify the cause by itself.

A cough may be dry and tickly or bring up mucus, also called phlegm or sputum. Mucus colour may change during an infection, but colour alone does not show whether antibiotics like amoxicillin or doxycycline are needed.

You may notice:

• A scratchy feeling or urge to clear your throat
• Sore chest or stomach muscles after frequent coughing
• Coughing that worsens at night, with exercise, or in cold air
• Wheezing or shortness of breath
• Coughing bursts that disrupt speaking or sleep
• Gagging or vomiting after a strong coughing spell

Note when the cough began, possible triggers, and whether you have fever, breathlessness, pain, or other symptoms.

Common causes include colds, influenza, COVID-19, and other viral respiratory infections. Airways may remain sensitive for several weeks after the infection settles.

Nasal mucus draining into the throat can trigger coughing during allergies, sinus problems, or a cold. Smoke, vaping, pollution, dust, perfumes, and cold air can also irritate the airways.

Asthma may cause cough, wheezing, chest tightness, or shortness of breath, especially at night or during exercise.

Other possible causes include acid reflux and ACE inhibitors like lisinopril or ramipril, a type of blood pressure medicine. Do not stop prescribed medicine without speaking to a clinician.

Whooping cough may cause repeated coughing attacks, vomiting, or a “whoop” when breathing in. Chronic lung conditions can also cause lasting coughs.

Less often, a persistent cough may be related to tuberculosis or lung cancer. Concern is greater with coughing blood, unexplained weight loss, ongoing fever, night sweats, or a history of smoking.

Call emergency services if you are struggling to breathe, cannot speak because of breathlessness, have blue or grey lips, become confused, have severe chest pain, or began coughing after choking.

Seek same-day medical care if you:

• Cough up blood, even a small amount
• Have new chest pain or breathing difficulty
• Feel very unwell or are worsening quickly
• Cannot keep fluids down or have signs of dehydration
• Have a weakened immune system and develop a new cough
• Have coughing attacks that interfere with breathing

Book a routine appointment if the cough lasts longer than three weeks, keeps returning, disrupts sleep, or affects daily activities. Arrange earlier follow-up for ongoing wheezing, fever, weight loss, night sweats, or worsening symptoms.

Babies, frail older adults, and people with serious heart or lung conditions may need earlier assessment.

A clinician will ask when the cough started, whether it produces mucus, and what affects it. They may ask about infections, allergies, heartburn, smoking or vaping, workplace exposures, travel, and medicines.

They may check your temperature and oxygen level, listen to your lungs, and examine your throat and nose.

Many short-lived coughs need no tests. Depending on your symptoms and the cough’s duration, tests may include an infection swab, chest X-ray, or breathing tests. Blood tests, mucus testing, or scans may be used when findings suggest they could help.

Treatment depends on the cause. Viral coughs usually improve without antibiotics, which do not treat viruses and are not routinely helpful for an uncomplicated acute cough.

While recovering:

• Drink enough fluid to avoid dehydration
• Try warm drinks or honey for soothing relief
• Avoid smoking, vaping, and second-hand smoke
• Rest and avoid known triggers
• Use saline nasal spray if congestion contributes

Do not give honey to a child younger than one year because of the risk of infant botulism.

Non-prescription cough and cold products have limited or mixed benefit. Check labels because combination products may duplicate ingredients in other medicines. Ask a pharmacist before using them during pregnancy, with a long-term condition, or alongside other medicines. Young children should not receive these products unless a healthcare professional advises it.

If asthma, reflux, allergies, or another condition is suspected, treatment can be tailored after assessment. Do not use someone else’s inhaler or stop prescribed medicine on your own.

A cough from a common respiratory infection often improves within three weeks, although mild coughing may continue for several weeks.

Symptoms should gradually become less frequent and intense. Seek reassessment if the cough worsens after improving, develops warning signs, or does not settle. Persistent coughing may require more than one visit because several factors can contribute.

Is a cough contagious?

The cough itself is not contagious, but an infection causing it may spread. Cover coughs, wash your hands, and follow local respiratory infection guidance.

Does green or yellow mucus mean I need antibiotics?

Not by itself. Mucus can change colour during an immune response. Other symptoms, examination findings, and sometimes tests determine whether antibiotics may help.

Why is my cough worse at night?

Lying down may increase nasal drainage or reflux, while asthma can worsen overnight. Discuss repeated nighttime coughing with a clinician, especially if it disrupts sleep or occurs with wheezing.

Should every cough be suppressed?

Not always. Coughing helps clear mucus. If a dry cough is painful or prevents sleep, a pharmacist or clinician can suggest suitable relief.