What causes wheezing?

Asthma can cause episodes of wheezing, cough, chest tightness, and breathlessness, often after exercise, cold air, smoke, or an allergen. Acute bronchitis may irritate the airways after a viral illness. Bronchiolitis can narrow the small airways in babies and young children. COPD can cause persistent or recurring wheeze, particularly with breathlessness and a long-term cough.

Allergic rhinitis usually affects the nose, but allergy-related inflammation can occur alongside lower-airway symptoms. Wheezing that starts suddenly after food, medicine, or an insect sting may be anaphylaxis, especially with swelling, hives, throat tightness, dizziness, or breathing difficulty. A clinician may listen to the chest and check oxygen, breathing effort, and response to treatment.

Move away from smoke, strong scents, dust, or a suspected trigger. Sit upright and use your prescribed reliever inhaler exactly as directed. If a clinician has supplied an asthma action plan, follow it. Do not borrow someone else's inhaler. A nebuliser treatment may be used by healthcare professionals when inhaled medicine needs to be delivered during significant breathing symptoms.

Call emergency services for severe breathlessness, blue or grey lips, inability to speak in full sentences, marked drowsiness, collapse, or swelling of the lips, tongue, or throat. Treat sudden wheezing after a possible allergen as an emergency, particularly when dizziness or widespread hives is present. Seek prompt assessment for a first episode, worsening symptoms, or wheezing that does not settle with your prescribed treatment.

Ask whether your pattern suggests asthma, infection, allergy, or COPD, and whether you need breathing tests or an inhaler plan. Tell the clinician when wheezing occurs, what triggers it, whether you cough at night, and whether you have fever, hives, swelling, or a new medicine.