What is the recommended dose of prednisone (corticosteroid) for an 18 kg child with an asthma exacerbation?

Prednisone Dosing for Pediatric Asthma Exacerbation

For an 18 kg child with an asthma exacerbation, administer oral prednisone at 1-2 mg/kg/day (18-36 mg/day) for 3-10 days, with no tapering required. 1

Weight-Based Dosing Calculation

• The recommended pediatric dose is 1-2 mg/kg/day in 2 divided doses, with a maximum of 60 mg/day 1, 2
• For an 18 kg child, this translates to 18-36 mg/day total 1
• The dose can be given as a single daily dose or divided into 2 doses throughout the day 1
• Most guidelines support using the full 2 mg/kg/day dose (36 mg for this child) for moderate-to-severe exacerbations 1, 2

Duration of Treatment

• Continue treatment for 3-10 days depending on severity and clinical response 1, 2
• For outpatient "burst" therapy, 5 days is typically sufficient and represents the standard of care 1
• No tapering is necessary for courses lasting less than 7-10 days, especially if the child will be started on inhaled corticosteroids 1, 2

Route of Administration

• Oral administration is strongly preferred and equally effective as intravenous therapy when gastrointestinal absorption is intact 1, 3
• A study comparing oral prednisone (2 mg/kg/dose twice daily) versus IV methylprednisolone in hospitalized children found no difference in length of stay, with oral therapy being substantially more cost-effective 3
• Reserve IV corticosteroids only for children who are vomiting or unable to tolerate oral medications 1

Clinical Algorithm for Severity-Based Dosing

• Mild exacerbations: May not require systemic steroids if responding well to bronchodilators 2
• Moderate exacerbations: Prednisone 1-2 mg/kg/day (18-36 mg for this child) for 5 days 1, 2
• Severe exacerbations: Prednisone 2 mg/kg/day (36 mg for this child) alongside aggressive bronchodilator therapy, continue until peak expiratory flow reaches 70% of predicted 1, 2

Critical Administration Details

• Administer the first dose immediately upon recognition of an exacerbation requiring systemic steroids 2
• Use a soluble prednisolone formulation for easier administration in young children 2
• Always combine prednisone with bronchodilator therapy (salbutamol via MDI with spacer), repeated every 20 minutes for the first hour if needed 2

Alternative Corticosteroid Option

• Single-dose dexamethasone 0.3 mg/kg (5.4 mg for this child) is a noninferior alternative to 3-5 days of prednisolone 4
• A randomized trial demonstrated that single-dose dexamethasone had equivalent efficacy to 3 days of prednisolone (1 mg/kg/day), with the advantage of eliminating compliance issues 4
• Dexamethasone has a longer half-life (36-72 hours) and may reduce vomiting compared to prednisolone 4

Important Clinical Pitfalls to Avoid

• Do not underdose: Using less than 1 mg/kg/day may result in treatment failure 1, 2
• Do not delay steroid administration while waiting for response to bronchodilators in moderate-to-severe cases 2
• Do not taper short courses: Tapering courses less than 7-10 days is unnecessary and may lead to underdosing during the critical recovery period 1
• Do not use unnecessarily high doses: Higher doses beyond 2 mg/kg/day have not shown additional benefit 1

When to Refer to Hospital

• Failure to respond to initial bronchodilator and oral steroid therapy within the first hour 2
• Severe breathlessness with increasing tiredness or inability to speak in full sentences 2
• Oxygen saturation <92% on room air 2
• No improvement after 5 days of treatment 2

Follow-Up Requirements

• Reassess within 48 hours if treated at home to ensure objective improvement 2
• Provide parents with a written asthma action plan 2
• Ensure the child is started on or continues inhaled corticosteroids at appropriate doses 2