What is the recommended dose of salbutamol (albuterol) for a child experiencing an acute asthma attack?

Salbutamol Dosing for Acute Asthma in Children

For acute asthma exacerbations in children, administer nebulized salbutamol at 0.15 mg/kg (minimum 2.5 mg) every 20 minutes for 3 doses initially, with weight-based dosing preferred: 2.5 mg for children <20 kg and 5 mg for children ≥20 kg. 1, 2

Initial Treatment Protocol

First Hour Management:

• Give nebulized salbutamol 0.15 mg/kg every 20 minutes for 3 doses 1, 2
• Use oxygen as the driving gas at 6-8 L/min flow rate to maintain oxygen saturation >92% 1, 2
• Administer oral prednisolone 1-2 mg/kg (or IV hydrocortisone 200 mg if vomiting) immediately 3
• Add ipratropium bromide 0.5 mg to the nebulizer if life-threatening features are present 4, 3

Weight-Based Dosing Specifics:

• Children <20 kg: 2.5 mg per dose 2
• Children ≥20 kg: 5 mg per dose 2
• Infants (e.g., 9-month-old weighing 8-10 kg): 1.2-1.5 mg per dose 1

This weight-based approach is critical because the British Thoracic Society explicitly warns against using the adult fixed dose of 5 mg in infants, as this represents excessive dosing and increases risk of tachycardia and tremors without additional benefit 1.

Alternative Delivery Method

Metered-Dose Inhaler (MDI) with Spacer:

• Administer 4-8 puffs (90 mcg/puff) every 20 minutes for 3 doses 2
• This method is equally effective as nebulization and actually preferred in infants when tolerated 1
• Research confirms comparable efficacy between MDI with spacer and nebulization in mild to moderate exacerbations 5, 6

Reassessment and Escalation (15-30 Minutes After Initial Treatment)

If inadequate response after initial 3 doses:

• Increase frequency to every 15-30 minutes 2
• Continue ipratropium 0.5 mg every 6 hours (mix with salbutamol in same nebulizer) 4, 3
• Consider continuous nebulization at 0.5 mg/kg per hour (maximum 10-15 mg/hour) 2
• Evaluate for IV salbutamol 15 mcg/kg over 10 minutes if severe deterioration 4, 7

Research demonstrates that adding IV salbutamol in severe cases reduces recovery time from 11.5 hours to 4 hours and decreases oxygen requirements significantly 7.

Ongoing Treatment After Stabilization

Once symptoms improve:

• Continue nebulized salbutamol at 0.15 mg/kg every 4-6 hours as needed 1
• Maximum daily dose: 40 mg/day during acute exacerbations 2
• Maintain oxygen saturation >92% throughout treatment 1, 3

Critical Pitfalls to Avoid

Do NOT:

• Use adult fixed doses (5 mg) in infants or small children—this causes excessive tachycardia without benefit 1
• Delay systemic corticosteroids—give prednisolone immediately with first salbutamol dose 3
• Underdose by using fixed 2.5 mg in larger children >20 kg—they require 5 mg 2
• Continue ineffective treatment without escalation—reassess at 15-30 minutes and adjust 3
• Use oral salbutamol syrup for acute bronchospasm—inhaled delivery provides superior bronchodilation with fewer systemic effects 2

Monitoring Requirements

Continuous assessment during treatment:

• Oxygen saturation via pulse oximetry 3
• Respiratory rate and work of breathing 2
• Heart rate (watch for excessive tachycardia) 2
• Clinical appearance and mental status 3

Hospital Transfer Criteria

Transfer immediately if:

• Life-threatening features present (silent chest, cyanosis, poor respiratory effort, confusion) 4, 3
• Peak expiratory flow remains <50% predicted after initial treatment 4, 3
• Persistent severe features despite 3 doses of salbutamol 3
• Deteriorating clinical status or worsening hypoxia 3

The British Thoracic Society emphasizes that severity of acute asthma is often underestimated, and objective measurements are essential to prevent fatal outcomes 4.