Why does bronchiectasis cause coughing up phlegm?

Healthy airways move mucus upward so it can be cleared. Bronchiectasis changes the airway shape and can slow that clearance, leaving mucus to collect. Coughing Up Phlegm is a very common presentation of Bronchiectasis. The volume, thickness, colour and smell of phlegm may vary; a clear change from your usual pattern can suggest irritation or infection and should be discussed with a clinician. Phlegm can also occur with colds, smoking-related disease, asthma and other respiratory conditions.

Use the airway-clearance techniques taught by your healthcare team, rather than repeatedly forcing a harsh cough. These techniques are designed to move mucus from smaller airways so it can be expelled with less strain. Keep regular review appointments and use prescribed inhalers or other treatments as directed. Contact your clinician if you are bringing up noticeably more phlegm, a new colour, a foul smell, or if breathlessness and tiredness are increasing.

Seek urgent medical help if breathlessness is severe or rapidly worsening, you have chest pain, blue or grey lips, confusion, high fever with marked illness, or you cough up blood. If phlegm makes it hard to breathe or you cannot clear it despite your usual plan, get prompt advice. These changes can need assessment for infection or airway blockage.

Ask for a demonstration of your mucus-clearance technique, whether a phlegm sample is needed during a flare, and what changes should trigger contact. Tell the team about recent antibiotics, inhaler use, vaccinations and any trouble completing your usual clearance routine.