Asthma
Symptoms, Causes & Treatment
Asthma is a common chronic respiratory condition causing reversible airway narrowing, inflammation, and hypersensitivity. It affects around 5.4 million people in the UK and is one of the most manageable long-term conditions with the right treatment plan.
What is Asthma?
Asthma is a chronic inflammatory condition of the airways characterised by reversible bronchoconstriction, airway inflammation, and bronchial hyperresponsiveness. The airways become swollen and sensitive, producing excess mucus and narrowing with exposure to triggers. Symptoms vary from mild intermittent wheeze to life-threatening attacks requiring emergency treatment. With a personalised management plan, the vast majority of people with asthma can achieve excellent symptom control.
Symptoms of Asthma
Asthma symptoms are characteristically variable — they may be absent between episodes and worsen at night, in the early morning, or with specific triggers.
Recurrent wheeze · Shortness of breath on exertion · Chest tightness, especially at night · Persistent dry cough, particularly at night or early morning · Symptoms triggered by exercise, cold air, allergens, or irritants · Variable symptoms that improve and worsen
Severe breathlessness at rest or with minimal exertion · Inability to complete sentences due to breathlessness · Silent chest on auscultation (no wheeze — indicates life-threatening asthma) · Cyanosis (blue lips or fingertips) · Peak flow less than 33% predicted · Confusion or reduced consciousness
You or someone else has severe breathlessness, is too breathless to speak, has a blue tinge to the lips, or the reliever inhaler is not helping. This is a life-threatening asthma attack.
What Causes Asthma?
Asthma is caused by airway inflammation and bronchial hypersensitivity. Multiple factors contribute to both the development of asthma and to individual attack triggers.
The most common form of asthma. Triggered by inhaled allergens such as house dust mites, pollen, pet dander, and mould spores. IgE-mediated mast cell activation causes bronchospasm and airway inflammation. Often associated with eczema and allergic rhinitis (the atopic triad).
Triggered by irritants rather than allergens — including cold air, exercise, smoke, pollution, strong smells, and viral respiratory infections. More common in adults and often harder to control than allergic asthma. NSAIDs and aspirin can trigger bronchoconstriction in susceptible individuals.
Exercise causes heat and water loss from the airways, triggering mast cell release and bronchospasm. Symptoms typically occur 5–15 minutes after exercise begins or just after stopping. Pre-exercise short-acting bronchodilators and warm-up strategies can prevent attacks.
Caused by workplace sensitisers including flour dust, isocyanates (paint spraying), latex, and animal proteins. It accounts for up to 15% of adult-onset asthma. Symptoms improve on days away from work. Early identification and removal from exposure are critical.
Chronic uncontrolled asthma causes permanent structural changes in the airways — subepithelial fibrosis, smooth muscle hypertrophy, and mucus gland hyperplasia. This leads to fixed airflow obstruction that becomes less reversible over time. Regular preventer therapy prevents remodelling.
Asthma has a strong genetic component — having a parent with asthma doubles a child's risk. Early childhood exposures (pollution, tobacco smoke, infections) influence immune programming. The hygiene hypothesis suggests reduced early microbial exposure may increase atopic disease risk.
Key Risk Factors
Diagnosing Asthma
Asthma diagnosis requires objective evidence of variable airflow obstruction. No single test is diagnostic — the clinical picture combined with investigations guides the diagnosis.
Treatment for Asthma
Asthma treatment follows a stepwise approach. The goal is the minimum treatment needed for complete symptom control, with regular review to step up or down.
Supportive Measures
Maintain a healthy weight, exercise regularly (with pre-treatment if needed), practice breathing exercises (Buteyko technique), reduce stress, and ensure bedroom is allergen-reduced with HEPA filters and allergen-proof bedding.
Managing Long-Term Asthma
Asthma requires regular review at least annually. At each review: assess symptom control using the Asthma Control Test (ACT), check inhaler technique, review trigger avoidance, update the written action plan, and step treatment up or down as appropriate.
When to Seek Help
Call 999 for any life-threatening asthma attack: severe breathlessness, unable to speak, silent chest, confusion, cyanosis, or deteriorating despite 10 puffs of salbutamol.
See a GP or asthma nurse if your reliever inhaler is needed more than 3 times a week, if symptoms are waking you at night, or if you have had an acute exacerbation. Review within 48 hours after any asthma attack.
Preventing Asthma Attacks
Most asthma attacks are preventable with consistent preventer therapy, trigger identification, and a clear action plan.
Use preventer inhaler every day as prescribed, even when feeling well. Stopping preventer therapy is the most common cause of poorly controlled asthma and preventable attacks.
Identify and reduce exposure to personal triggers — house dust mites, pet dander, pollen, mould, smoke, and cold air. Allergen-proof mattress and pillow covers significantly reduce house dust mite exposure.
Annual flu vaccine and one-off pneumococcal vaccine are recommended for all asthma patients. Respiratory infections are the most common cause of asthma exacerbations.
Smoking worsens asthma severity, reduces response to inhaled corticosteroids, and accelerates lung function decline. Stopping smoking is the single most effective intervention for adult asthma.
An asthma action plan sets out what to do when symptoms worsen. Written plans significantly reduce hospital admissions. Review with GP or asthma nurse at least annually.
Regular aerobic exercise improves cardiovascular fitness and lung function in asthma patients. Pre-exercise salbutamol and a 10-minute warm-up reduce exercise-induced symptoms.
Getting Treatment for Asthma
A GP can diagnose asthma, prescribe inhalers, and manage all steps of the asthma ladder. An online GP consultation is an effective first step for new respiratory symptoms, inhaler reviews, or treatment changes.
Expert clinical advice, when you need it.
Asthma — Frequently Asked Questions
Asthma cannot currently be cured but can be very effectively controlled. Most people with well-managed asthma lead completely normal, active lives. Regular preventer therapy, trigger avoidance, and an action plan are the cornerstones of good control.
You should use your reliever (blue) inhaler whenever you have symptoms. If you need it more than 3 times a week, your asthma is not well controlled and you should book a review with your GP or asthma nurse to step up treatment.
Yes. Viral respiratory infections, particularly rhinovirus (the common cold), are the most common trigger for asthma attacks in both adults and children. Annual flu vaccination significantly reduces exacerbation risk.
At the correct inhaled doses, corticosteroid preventers are very safe. The amount of steroid reaching the bloodstream is tiny compared to oral steroids. Side effects are mainly local — oral thrush and hoarseness — prevented by rinsing your mouth after each dose.
For a mild attack: sit upright, take 1 puff of salbutamol every 30–60 seconds up to 10 puffs, and call 999 if not improving. Do not lie down. If you run out of your inhaler, call 999. Never ignore a worsening attack.
Yes. Most people with well-controlled asthma can exercise safely. Pre-exercise salbutamol and a gradual warm-up prevent exercise-induced symptoms. Swimming is particularly well-tolerated. Exercise itself improves asthma control over time.
Asthma can improve in adult life, though it rarely disappears completely. Many children with mild asthma see significant improvement in adolescence. However, symptoms often return in adulthood — particularly in women during hormonal changes.
Your GP can diagnose asthma, prescribe inhalers, and manage asthma at all levels. An online GP consultation is an effective first step for new symptoms, inhaler reviews, or treatment changes. Hospital referral is needed for severe or refractory asthma.