Asthma
NHS 25 March 2026
What is Asthma?
Asthma is a common condition that affects the airways in your lungs. When triggered, the airways become inflamed, narrow and produce extra mucus, making breathing difficult. Around 5.4 million people in the UK are currently receiving treatment for asthma.
Symptoms
- Wheezing (a whistling sound when breathing)
- Breathlessness
- Chest tightness
- Coughing, especially at night or early morning
Common Triggers
- Respiratory infections (colds, flu)
- Allergens (pollen, dust mites, pet dander, mould)
- Exercise
- Cold air or weather changes
- Pollution and smoke
- Strong emotions or stress
- Certain medicines (aspirin, NSAIDs, beta-blockers)
Diagnosis
Your GP will ask about your symptoms and carry out breathing tests (spirometry, peak flow). These tests check how well your lungs are working and whether there is a blockage in the airways.
Treatment
- Reliever inhaler (usually blue) — for immediate symptom relief; contains a short-acting beta2-agonist (SABA) like salbutamol
- Preventer inhaler (usually brown) — taken daily to reduce airway inflammation; contains an inhaled corticosteroid (ICS)
- Combination inhalers — contain both a corticosteroid and a long-acting beta2-agonist (LABA) for more severe asthma
Asthma Action Plan
Everyone with asthma should have a written asthma action plan from their GP or asthma nurse. This tells you what to do when your symptoms get worse and when to seek emergency help.