Child Asthma — Symptoms, Triggers, Inhalers & Management Guide — Symptoms, Causes & Treatment | MyMedicPlus

Asthma is a chronic inflammatory disease of the airways characterised by variable airflow obstruction and bronchial hyperresponsiveness. It is the most common chronic condition in children worldwide, affecting approximately 14% of children (339 million people of all ages globally). In children, the airways are smaller and more reactive, making symptoms more pronounced. Typical childhood asthma involves episodic wheeze, cough (particularly at night or early morning), shortness of breath, and chest tightness — triggered by viral respiratory infections, allergens (house dust mite, pets, pollen), exercise, cold air, and cigarette smoke. Asthma is also the leading cause of school absenteeism from chronic illness in high-income countries. Up to 5.4 million people in the UK live with asthma, of whom 1.1 million are children. The 2023 National Review of Asthma Deaths showed that 85% of asthma deaths are preventable with correct preventer inhaler prescribing and patient education.

Childhood asthma has a strong genetic component — children with one asthmatic parent have a 30% risk; with two asthmatic parents, the risk rises to 70%. Atopy (eczema, allergic rhinitis, food allergy) is a major risk factor. Environmental triggers that precipitate attacks: viral respiratory infections (RSV and rhinovirus most important in young children), allergens (house dust mite is the most common — found in mattresses, carpets, soft toys; pet dander; cockroach; mould spores; grass and tree pollen), cigarette smoke exposure (active and passive), cold/dry air, exercise, strong odours, and emotional stress. Air pollution (particulate matter, ozone, nitrogen dioxide) worsens asthma control.

Classic symptoms of childhood asthma include: persistent cough (often the only symptom in very young children — especially nocturnal cough between 2-4 am or exercise-induced); wheeze (a high-pitched musical sound on expiration); breathlessness (difficulty speaking full sentences); and chest tightness. Symptoms are typically episodic, variable, and worse at night. Severe acute asthma attack (status asthmaticus) signs requiring emergency care: inability to complete sentences, accessory muscle use, silent chest (absent breath sounds — critically severe), SpO2 below 92%, heart rate above 125/min in children, and agitation or confusion. Call emergency services immediately for severe attacks. In very young children (under 3 years), episodic viral wheeze — triggered exclusively by respiratory infections without atopy — is common and often resolves by school age without becoming true asthma. Multitrigger wheeze (from infections AND allergens, exercise, or cold air) in atopic children under 3 is more predictive of persistent asthma.

Asthma diagnosis in children is primarily clinical, based on pattern of symptoms, triggers, and personal/family atopic history. Spirometry (FEV1, FVC, FEV1/FVC ratio) with bronchodilator reversibility testing (salbutamol 400 mcg — significant reversibility: FEV1 increase of over 12% and 200 mL) confirms airflow obstruction and variable reversibility. In children under 5, spirometry is often not feasible — diagnosis based on clinical assessment, response to treatment trial, and symptom patterns. Peak flow variability (over 20% diurnal variation) supports the diagnosis. Fractional exhaled nitric oxide (FeNO — above 35 ppb) indicates eosinophilic airway inflammation, predicting steroid responsiveness. Allergy skin prick testing or specific IgE identifies allergen sensitisation. Chest X-ray is not diagnostic for asthma but excludes other pathology.

Inhaler technique and spacer use are fundamental — all children under 5 (and many up to 12 years) should use a pressurised metered-dose inhaler (pMDI) with a spacer device (e.g., AeroChamber) for all inhaled medications, as this dramatically improves drug delivery to the lungs. BTS/SIGN/NICE step-wise management: Step 1 — short-acting beta-2 agonist (SABA) reliever inhaler (salbutamol/Ventolin) for symptom relief; Step 2 — add inhaled corticosteroid (ICS) preventer (beclometasone, fluticasone, budesonide) — taken daily even when well; Step 3 — add long-acting beta-2 agonist (LABA) salmeterol or formoterol (not licensed as monotherapy in children); Step 4 — specialist referral; consider montelukast, high-dose ICS, theophylline. Biologics (dupilumab, mepolizumab) for severe eosinophilic asthma. Every child with asthma should have a written Asthma Action Plan detailing preventer/reliever use, warning signs, and when to seek emergency care.

Uncontrolled or under-treated childhood asthma results in acute life-threatening attacks, status asthmaticus requiring intensive care, and preventable asthma deaths — in the UK, 179 children and young people under 19 died from asthma in 2021, the majority considered preventable with adequate preventer therapy. Chronic poorly controlled asthma drives airway remodelling — subepithelial fibrosis, smooth muscle hypertrophy, and mucous gland enlargement — causing irreversible fixed airflow limitation persisting into adulthood. Children with uncontrolled asthma achieve a lower peak lung function during the critical developmental window of early adulthood. Recurrent severe attacks requiring oral steroids carry risks of adrenal suppression, growth suppression, and osteoporosis. Anxiety and depression affect 25-40% of children with severe asthma.

Reduce exposure to known triggers: encase mattresses and pillows in allergen-proof covers; wash bedding weekly at 60 degrees Celsius to kill dust mites; avoid having pets if sensitised; keep indoor humidity below 50% to reduce dust mite and mould growth; avoid cigarette smoke entirely. Give the preventer inhaler every day as prescribed, even when the child feels well — skipping it leads to poorly controlled inflammation and increased attack risk. Always carry the reliever inhaler. Annual flu vaccination is recommended for all children with asthma. Encourage and support regular exercise — well-controlled asthma should not prevent participation in sports and physical education. Review inhaler technique at every consultation. Use a written Asthma Action Plan and share with school staff.

Call 999/112 immediately (emergency services) for: a severe asthma attack where the child cannot complete a sentence or speak in phrases, has blue lips (cyanosis), is silent on auscultation (silent chest — critically severe, indicating little or no airflow), or fails to improve after 10 puffs of salbutamol reliever inhaler with a spacer. While waiting for the ambulance, continue giving salbutamol every 20 minutes. See a GP urgently the same day for: a reliever inhaler needed more than every 4 hours, an acute attack not fully resolved within 24 hours with home treatment, or any child whose symptoms are worsening despite following the Asthma Action Plan. Every child with asthma should have a written Asthma Action Plan — if your child does not have one, ask their GP or paediatrician to provide one. Routine asthma review is recommended at least annually — children with poorly controlled asthma (using reliever more than 3 times per week, or waking at night) need earlier review and possibly step-up of treatment.