What is the best approach to manage allergy-triggered asthma?

Management of Allergy-Triggered Asthma

Subjective

Chief Complaint & History of Present Illness:

• Document specific allergic triggers (pollens, dust mites, animal dander, molds, cockroaches) and temporal relationship between exposure and asthma symptoms 1
• Quantify current impairment: frequency of daytime symptoms, nighttime awakenings per week, use of short-acting beta-agonist (SABA) for symptom relief (not exercise prevention), and activity limitations 1
• Assess risk factors: history of severe exacerbations requiring emergency department visits, hospitalizations, or oral corticosteroids in past year 1
• Identify comorbid conditions that worsen asthma: allergic rhinitis, sinusitis, gastroesophageal reflux disease, obesity, obstructive sleep apnea 1, 2
• Review environmental exposures: tobacco smoke, occupational irritants, indoor allergens 1

Medication History:

• Current controller medications, adherence patterns, and perceived effectiveness 1
• Frequency of SABA use (>2 days/week indicates inadequate control) 1
• Previous response to inhaled corticosteroids (ICS) and other controllers 1

Objective

Physical Examination:

• Respiratory rate, use of accessory muscles, wheezing on auscultation, prolonged expiratory phase 1
• Signs of allergic disease: allergic shiners, nasal polyps, eczema 1

Spirometry (required for patients ≥5 years):

• Pre-bronchodilator FEV1 and FEV1/FVC ratio to document airflow obstruction 1
• Post-bronchodilator response (≥12% and ≥200 mL improvement in FEV1 confirms reversibility) 1

Allergy Testing:

• Skin testing or serum-specific IgE testing is mandatory for persistent asthma to identify specific allergen sensitivities 1
• Focus on perennial indoor allergens (dust mites, cockroaches, rodents, molds, animal dander) 1

Fractional Exhaled Nitric Oxide (FENO):

• Consider FENO measurement (≥25 ppb in adults, ≥20 ppb in children suggests eosinophilic inflammation) when diagnosis is uncertain or to guide anti-inflammatory therapy selection 1

Assessment

Classify Asthma Severity (for patients not on controller therapy):

• Intermittent: Symptoms ≤2 days/week, nighttime awakenings ≤2 times/month, SABA use ≤2 days/week, no interference with normal activity 1
• Mild Persistent: Symptoms >2 days/week but not daily, nighttime awakenings 3-4 times/month 1
• Moderate Persistent: Daily symptoms, nighttime awakenings >1 time/week but not nightly, some limitation of normal activity 1
• Severe Persistent: Symptoms throughout the day, nighttime awakenings often 7 times/week, extremely limited activity 1

Assess Asthma Control (for patients on controller therapy):

• Well-controlled, not well-controlled, or very poorly controlled based on impairment and risk domains 1
• SABA use >2 days/week for symptom relief indicates inadequate control and need to step up treatment 1

Plan

Pharmacologic Management: Stepwise Approach

Step 1 (Intermittent Asthma):

• SABA as needed (albuterol 2 puffs every 4-6 hours as needed) 1

Step 2 (Mild Persistent Asthma):

• Preferred for ages ≥12 years: Either daily low-dose ICS plus as-needed SABA, OR as-needed ICS-formoterol used concomitantly 1
• Preferred for ages 5-11 years: Daily low-dose ICS plus as-needed SABA 1
• Alternative: Leukotriene receptor antagonist (montelukast 10 mg daily for adults, 5 mg for ages 6-14 years) or cromolyn 1
• Note: FDA issued Boxed Warning for montelukast regarding neuropsychiatric events including suicidal thoughts 1

Step 3 (Moderate Persistent Asthma):

• Preferred for ages ≥12 years: Low-dose ICS-LABA combination (e.g., fluticasone-salmeterol 100/50 mcg twice daily or budesonide-formoterol 80/4.5 mcg twice daily) 1
• Equally preferred alternative: Medium-dose ICS alone 1
• Preferred for ages 5-11 years: Medium-dose ICS 1

Step 4 (Moderate-Severe Persistent Asthma):

• Preferred: Medium-dose ICS-LABA combination 1
• Alternative: Medium-dose ICS plus leukotriene receptor antagonist or theophylline 1

Step 5 (Severe Persistent Asthma):

• Preferred: High-dose ICS-LABA combination 1
• Consider omalizumab (anti-IgE) for patients ≥12 years with allergic asthma, elevated serum IgE, and inadequate control on high-dose ICS-LABA 1
• Dosing: 150-375 mg subcutaneously every 2-4 weeks based on IgE level and weight 1
• Warning: Clinicians must be prepared to treat anaphylaxis when administering omalizumab 1

Step 6 (Severe Uncontrolled Asthma):

• High-dose ICS-LABA plus oral corticosteroids 1
• Consider omalizumab or other biologics (mepolizumab, reslizumab, benralizumab, dupilumab) targeting type-2 inflammation 2

ICS-Formoterol as Maintenance and Reliever Therapy (MART):

• For ages ≥4 years with moderate-severe persistent asthma: ICS-formoterol in a single inhaler used as both daily controller and reliever therapy is strongly recommended over higher-dose ICS alone or same-dose ICS-LABA with SABA for quick relief 1
• This approach significantly reduces severe exacerbations 1, 3

Allergen-Specific Interventions

Environmental Control:

• Multicomponent allergen-specific mitigation strategies are conditionally recommended for patients with confirmed sensitization and symptoms related to identified indoor allergens 1
• Single interventions alone are generally ineffective 1

For Dust Mite Allergy:

• Impermeable pillow and mattress covers only as part of multicomponent strategy, not as single intervention 1
• Remove carpets, feather pillows, quilts from bedroom 1, 4
• Use HEPA filters or electrostatic air filters 1, 4

For Pest Allergens (Cockroaches, Rodents):

• Integrated pest management alone or as part of multicomponent intervention is conditionally recommended 1

For Animal Dander:

• Remove pets from home if sensitized and symptomatic 1, 4

Tobacco Smoke:

• Mandatory avoidance of all tobacco smoke exposure 1

Allergen Immunotherapy

Subcutaneous Immunotherapy (SCIT):

• Consider for patients with allergic asthma requiring Step 2-4 care (mild-moderate persistent) when clear relationship exists between symptoms and unavoidable allergen exposure 1
• Evidence strongest for single allergens including pollens, dust mites, and animal danders 1, 5
• Clinicians must be prepared to treat anaphylaxis 1
• May decrease risk of asthma development in patients receiving immunotherapy for allergic rhinitis 2

Sublingual Immunotherapy:

• Efficacy supported by meta-analyses for allergic asthma 5

Patient Education & Self-Management

Written Asthma Action Plan (mandatory):

• Instructions for daily management: long-term controller medications, environmental control measures 1, 6
• Instructions for managing worsening asthma: when to increase quick-relief medication, when to start oral corticosteroids, when to seek emergency care 1, 6
• Doubling ICS dose at home for worsening symptoms is NOT effective and should not be recommended 1

Inhaler Technique:

• Assess and correct at every visit before stepping up therapy 1

Peak Flow Monitoring:

• Particularly helpful for patients with difficulty perceiving symptoms, history of severe exacerbations, or moderate-severe asthma 1

Education Settings:

• Provide education at all points of care: clinic visits, emergency departments, hospitals, pharmacies, schools, community settings, patients' homes 1

Monitoring & Follow-Up

Assess Control at Every Visit:

• Frequency of symptoms, nighttime awakenings, SABA use, activity limitation 1
• Spirometry periodically to assess lung function 1
• FENO measurement if used as part of ongoing monitoring strategy (not in isolation) 1

Step Down Therapy:

• If asthma well-controlled for ≥3 consecutive months, consider stepping down to identify minimum medication needed 1

Step Up Therapy:

• First verify adherence, inhaler technique, environmental control, and comorbid conditions before stepping up 1
• Reassess in 4-6 weeks after step up 1

Specialist Referral:

• Consider at Step 2, mandatory at Step 3 or higher 1
• Difficulties achieving or maintaining control 1
• When omalizumab or other biologics considered 1

Management of Acute Exacerbations

Outpatient Management:

• Albuterol 2-4 puffs every 20 minutes for up to 1 hour 1, 6
• Oral corticosteroids (prednisone 40-60 mg daily for 5-7 days) for moderate-severe exacerbations 1, 6
• Consider short course of oral corticosteroids at discharge from emergency department 1

Emergency Department Criteria:

• FEV1 or peak flow <40% predicted indicates severe exacerbation 1
• Goal for discharge: ≥70% predicted FEV1 or peak flow 1

Common Pitfalls to Avoid

• Never use LABA as monotherapy (FDA black box warning) 1
• Do not rely on SABA alone for persistent asthma 1
• Do not ignore environmental triggers—single interventions are ineffective 1
• Do not step up therapy without first checking adherence and inhaler technique 1
• Do not use FENO in isolation to assess control or predict exacerbations 1