Role of Prednisolone in Managing Asthma Exacerbations Triggered by Viral Infections
Systemic corticosteroids like prednisolone are essential for treating asthma exacerbations triggered by viral infections and should be administered early in the treatment course to reduce hospital admission rates and risk of relapse. 1
Mechanism and Importance
- Viral infections, especially rhinovirus, are the most common triggers for asthma exacerbations, causing neutrophilic inflammation of the upper and lower airways 2
- Systemic corticosteroids address the inflammatory component of asthma exacerbations, though their anti-inflammatory effects may take 6-12 hours to become apparent 3
- Underuse of corticosteroids is associated with increased mortality in asthma exacerbations 1
Dosing Recommendations
- For adults with moderate to severe exacerbations: Oral prednisone/prednisolone 40-60 mg daily until peak expiratory flow (PEF) reaches 70% of predicted or personal best 2, 1
- For children: 1-2 mg/kg body weight daily (maximum 60 mg/day) for 3-10 days; no tapering of this dose is needed for short courses 2
- For outpatient management: A "burst" of 40-60 mg in single or divided doses for a total of 5-10 days 2, 1
- Higher doses (0.6 mg/kg) have been shown to be more effective than lower doses (0.2-0.4 mg/kg) in treating exacerbations 4
Route of Administration
- Oral administration is preferred when gastrointestinal absorption is not compromised 2, 3
- No known advantage exists for intravenous administration over oral therapy when gastrointestinal transit time or absorption is not impaired 2, 5
- For patients who are seriously ill or vomiting, intravenous administration may be necessary 1
Treatment Algorithm Based on Severity
- Mild exacerbations (PEF ≥70% predicted/personal best): May not require systemic corticosteroids 1
- Moderate exacerbations (PEF 40-69% predicted/personal best): Oral systemic corticosteroids and frequent inhaled short-acting beta-agonists 1
- Severe exacerbations (PEF <40% predicted/personal best): Immediate administration of systemic corticosteroids 1
- Life-threatening exacerbations (PEF <25% predicted/personal best): Immediate systemic corticosteroids with consideration for hospitalization 1
Indications for "Rescue" Corticosteroid Courses
- Symptoms and PEF getting progressively worse day by day 2
- PEF falls below 60% of patient's best 2
- Sleep is disturbed by asthma 2
- Morning symptoms persist until midday 2
- Diminishing response to inhaled bronchodilators 2
- Emergency use of nebulized or injected bronchodilators 2
Monitoring Treatment Response
- Measure PEF 15-30 minutes after starting treatment and then according to response 1
- Monitor for clinical improvement, including reduced work of breathing, decreased respiratory rate, and improved PEF 1
- Continue treatment until PEF reaches 70% of predicted or personal best 2
Important Considerations
- Antibiotics are not generally recommended for asthma exacerbations as viruses are a much more common cause than bacteria 2
- Antibiotics should be reserved for cases with strong evidence of bacterial infection (e.g., pneumonia or sinusitis) 2
- For corticosteroid courses of less than 1 week, there is no need to taper the dose 2
- Dexamethasone may be considered as an alternative to prednisolone, with some studies showing faster action and minimal side effects 6
Common Pitfalls to Avoid
- Underestimating the severity of asthma exacerbations, leading to inadequate treatment 1
- Delaying corticosteroid administration, which worsens outcomes 3, 1
- Overreliance on bronchodilators without addressing the underlying inflammation 2
- Using antibiotics unnecessarily when viral infection is the trigger 2