Heat-induced asthma: what to know

Hot air can carry irritants and may feel harder to breathe, while humidity, dust, mould, pollen and air pollution can inflame sensitive airways. Some people develop cough, wheezing, chest tightness or shortness of breath during outdoor activity in hot weather. Allergic rhinitis and house dust mite allergy may add to airway irritation. Symptoms do not prove that heat is the sole trigger, so timing and surroundings are useful clues.

Follow your written asthma action plan and keep prescribed reliever medicine accessible. Move to a cooler, cleaner-air place, stop exertion and breathe slowly. Avoid smoky or dusty areas, check local air-quality advice and drink fluids regularly. Warm up gradually before exercise and discuss prevention with a clinician if hot-weather episodes recur. Never change controller treatment without medical guidance.

Call emergency services if breathing is severely difficult, speech is limited, lips look blue, the person is exhausted or the reliever is not helping as directed. Prompt review is needed for night waking, increasing reliever use, repeated attacks or a cough that persists. A nebuliser treatment may be used in urgent care when clinically appropriate.

Ask which triggers to record, how to adjust activity in heat, how to use your inhalers correctly, and when symptoms require urgent treatment.