What should you know about wheezing on expiration?

The outward breath can compress small airways, making narrowing easier to hear. Asthma often causes variable symptoms, with wheeze linked to exercise, cold air, allergens or a respiratory infection. Acute bronchitis can create temporary swelling and mucus. COPD may cause ongoing airflow limitation. In babies, bronchiolitis can lead to wheeze and faster breathing. A sudden reaction involving wheeze, rash or swelling is different and may represent anaphylaxis.

Consider whether the sound is on one side or both, whether it occurs at rest, and whether you feel chest tightness or breathlessness. A recording may help a clinician understand what you heard, but it cannot replace an examination.

Stop exertion and sit upright. Keep away from smoke, vaping aerosol, dust and strong odours. If you have an individual asthma or COPD plan, use it as prescribed. Do not start antibiotics or someone else’s inhaler without medical advice. Seek a routine assessment for a first or repeated episode, particularly when it limits activity or interrupts sleep.

Call emergency services for rapidly worsening breathing, blue or grey skin, severe chest tightness, fainting, confusion or inability to speak in full phrases. Wheeze with tongue or throat swelling after an exposure is an emergency. For infants and children, urgent help is needed when breathing is visibly laboured, pauses occur, or the child is too tired to drink.

What examination or breathing test would help identify the cause? Is there a pattern to the trigger or time of day? Which prescribed treatment should I use if the wheeze returns, and when should I attend urgent care?