Asthma

What is asthma?

Asthma is a long term condition in which the airways are inflamed and react excessively to triggers, narrowing and producing mucus. The narrowing is typically reversible, which distinguishes asthma from COPD. Well controlled asthma should allow a normal active life, and frequent reliever inhaler use is a signal that control needs review.

Causes

• Airway inflammation with hyperresponsiveness
• Allergic sensitisation to dust mite, pollen or animal dander
• Viral respiratory infections
• Occupational exposure to dusts and chemicals
• Air pollution and tobacco smoke

Symptoms

• Wheeze, usually on breathing out
• Shortness of breath
• Chest tightness
• Cough that is often worse at night or early morning
• Symptoms triggered by exercise, cold air or allergens

Risk factors

• Personal or family history of allergy or eczema
• Childhood respiratory infections
• Tobacco smoke exposure including in pregnancy
• Obesity
• Occupational irritant exposure

Diagnosis

• Symptom pattern and trigger history
• Spirometry showing reversible airflow obstruction
• Peak expiratory flow variability over time
• Fractional exhaled nitric oxide testing where available
• Allergy testing when an allergic trigger is suspected

Treatment

• Inhaled corticosteroid as the foundation of control
• Combination inhaled corticosteroid and long acting bronchodilator
• Reliever inhaler for acute symptoms
• Written personal asthma action plan
• Trigger identification and avoidance
• Biologic therapy for severe eosinophilic asthma

Self care

• Use your preventer inhaler every day, even when you feel well
• Learn and check your inhaler technique, ideally with a spacer
• Follow your written asthma action plan
• Track peak flow readings if advised
• Identify and reduce your triggers at home and work
• Keep up with influenza and COVID-19 vaccination
• Stop smoking and avoid second hand smoke

When to see a doctor

Book an appointment if:

• Needing your reliever inhaler more than twice a week
• Waking at night with cough, wheeze or breathlessness
• Symptoms limiting exercise or daily activity
• Using more than one reliever inhaler in a month
• Any hospital or emergency visit for asthma
• Before pregnancy, so treatment can be reviewed

Some symptoms need emergency care rather than an appointment. See the warning signs listed above.

Prevention

• Take preventer treatment consistently to reduce airway inflammation
• Reduce exposure to dust mite, pets, pollen or mould where these trigger you
• Avoid smoking, including during pregnancy
• Warm up properly before exercise
• Treat hay fever, since nasal and lung inflammation are linked
• Keep to a healthy weight

Outlook

Most people with asthma can live a normal, fully active life when treatment is taken consistently and technique is correct. Symptoms often improve through childhood, though the underlying tendency can persist and may return later. Poorly controlled asthma carries a real risk of severe attacks, so regular review matters more than how well someone feels on any given day.

Related conditions

Common questions