What should you know about cough in the lungs?

Acute bronchitis often causes a cough after a respiratory infection, with or without mucus. Asthma may cause cough, wheezing or chest tightness, especially after triggers or at night. Bronchiectasis can lead to a long-lasting productive cough because widened airways do not clear mucus normally. Bronchiolitis affects the smallest airways, mainly in young children. Allergic rhinitis may cause drainage from the nose into the throat, while acid reflux can irritate the upper airway. A cough lasting a long time deserves assessment even when there is no fever.

Drink enough fluid to avoid dehydration, avoid smoke and vaping, and use a clean humidified environment if it feels soothing. Note whether the cough is dry or brings up mucus, whether it follows meals or exercise, and whether breathing is noisy. Do not start leftover antibiotics: many coughs are caused by irritation or viruses, and treatment depends on the cause. A clinician may listen to your chest and review medicines, allergies, reflux symptoms and exposure to dust or fumes.

Seek emergency help for severe breathing difficulty, chest pressure, blue lips, confusion, or coughing a significant amount of blood. Arrange prompt assessment for chest pain with breathing, worsening breathlessness, high or persistent fever, dehydration, or a cough that is not improving. Children, older adults and people with long-term lung disease may need earlier review. Bring a list of medicines and describe any mucus colour without assuming it proves a bacterial infection.

Could asthma, reflux or nasal drainage be contributing? Do I need lung-function testing or imaging? What changes in my breathing should prompt urgent help?