What is the recommended salbutamol (albuterol) dose and administration schedule for a child with wheeze, including weight‑based nebulised dosing for infants and older children, MDI with spacer dosing for different age groups, and adjustments for severe exacerbations?

Salbutamol Dosing for Pediatric Patients with Wheeze

For children presenting with acute wheeze, administer nebulized salbutamol at 0.15 mg/kg (minimum 2.5 mg) every 20 minutes for three consecutive doses during the first hour, then continue every 1–4 hours as needed based on clinical response. 1

Weight-Based Nebulized Dosing by Age Group

Infants and Young Children (<5 years)

• Initial treatment: 0.15 mg/kg per dose (minimum 2.5 mg regardless of calculated weight-based dose) every 20 minutes for three doses 2, 1
• Maintenance: 2.5 mg every 1–4 hours as needed, adjusting frequency based on symptom severity 2, 1
• Critical point: Never administer less than 2.5 mg per dose, even when weight-based calculations suggest a lower amount (e.g., for a 9 kg infant, the calculated 1.35 mg dose should be rounded up to the 2.5 mg minimum) 1
• Delivery consideration: Some infants cannot tolerate face masks and spacers, in which case nebulizers are essential 2

Older Children (5–11 years)

• Initial treatment: 0.15 mg/kg (typically 2.5–5 mg) every 20 minutes for three doses 2
• Maintenance: 2.5–5 mg every 1–4 hours as needed 2, 1
• Severe exacerbations: May use 5 mg per dose or double the usual dose 2

Adolescents (≥12 years)

• Use adult dosing: 2.5–5 mg every 20 minutes for three doses, then every 1–4 hours as needed 1

MDI with Spacer Dosing (Alternative to Nebulizer)

Children Under 4 Years

• Dose: 100 mcg per puff (standard albuterol MDI delivers 90 mcg/puff) 2, 3
• Initial treatment: 4–8 puffs every 20 minutes for three doses 1, 3
• Maintenance: 4–8 puffs every 1–4 hours as needed 3
• Device: Must use valved holding chamber (spacer) with face mask 3
• Efficacy note: MDI with spacer is equally effective as nebulized therapy for mild-to-moderate exacerbations when proper technique is used 2, 1, 4

Children 4–11 Years

• Dose: Same as above (4–8 puffs per treatment session) 2, 3
• Can use spacer with mouthpiece instead of face mask 3

Adolescents (≥12 years)

• Follow adult MDI dosing: 4–8 puffs every 20 minutes for three doses 3

Severe Exacerbation Adjustments

Life-Threatening Features

Watch for: cyanosis, silent chest, poor respiratory effort, fatigue/exhaustion, agitation, reduced consciousness, inability to speak or feed, PEF <33% predicted 2, 1

Continuous Nebulization Protocol

• Indication: Failure to respond to standard intermittent dosing or life-threatening exacerbations 2, 1
• Dose: 0.5 mg/kg/hour (approximately 4.5–5.5 mg/hour for a typical 1-year-old; 10–15 mg/hour for adolescents) 1, 3
• Setting: Requires intensive care monitoring 2, 1

Adjunctive Ipratropium Bromide

• Add to moderate-to-severe exacerbations: 250 mcg (0.25 mg) mixed with each of the first three salbutamol doses 2, 1
• Discontinue after third dose unless child requires hospitalization 1, 3
• Evidence: Combined therapy significantly reduces hospitalization rates in severe exacerbations 3, 5

Nebulizer Administration Technique

Preparation

• Dilute each dose to minimum 3 mL total volume with normal saline to optimize aerosol generation 1, 3
• Driving gas: Use oxygen at 6–8 L/min flow rate when feasible 2, 1, 3

Special Consideration for Bronchiolitis

• Therapeutic trial recommended: Administer salbutamol to all 1-year-olds with acute wheeze; clinical response helps differentiate bronchiolitis from asthma-related wheeze 1
• Reassess after 2–3 doses: If no improvement, the episode may be bronchiolitis with minimal bronchodilator-responsive component 1
• Do not delay treatment while attempting diagnostic distinction 1
• Evidence caveat: One study found no significant benefit of regular salbutamol in wheezy infants under 1 year with atopic background, but this does not preclude therapeutic trials in acute settings 6

Monitoring and Safety

After Each Treatment Assess

• Respiratory rate, work of breathing, wheezing intensity, oxygen saturation 1, 3
• Common side effects: Tachycardia, tremor (usually well tolerated) 2, 1, 3
• Less common: Hypokalemia, especially with frequent or high-dose administration 3

Signs Requiring Escalation

• Inability to feed or speak, altered mental status, severe retractions, worsening fatigue, persistent hypoxemia 1, 3
• Lack of response after three doses warrants senior clinician review and possible ICU transfer 2, 1

Transition to Discharge Therapy

• Switch to MDI with spacer 24–48 hours before discharge once clinical improvement is demonstrated 2, 1
• Continue nebulizations until: PEF exceeds 75% predicted and diurnal variability falls below 25% 1

Common Pitfalls to Avoid

1. Never underdose in acute settings: The minimum 2.5 mg threshold and three-dose, 20-minute interval regimen are critical for adequate bronchodilation 1

2. Do not continue ipratropium beyond first three doses once hospitalized, as additional benefit has not been demonstrated 3

3. Avoid increasing frequency beyond every 1–2 hours for >24 hours: This indicates inadequate control requiring controller therapy (inhaled corticosteroids) or hospitalization, not simply more bronchodilator 1

4. Do not substitute MDI for nebulizer in severe exacerbations without confirming adequate response; nebulized therapy provides more reliable drug delivery when airways are severely constricted 3

5. Regular use exceeding twice weekly for symptom control indicates poor asthma control and requires reassessment of controller medication 2, 1