What is the best course of treatment for a patient with a history of asthma, currently experiencing expiratory wheezing after exposure to a dog, and taking bupropion and risperidone?

Management of Acute Asthma Exacerbation Triggered by Dog Allergen Exposure

Immediately administer a short-acting inhaled beta-agonist (salbutamol 400 μg by metered-dose inhaler with spacer, or 5 mg via nebulizer) and give oral prednisolone 30-60 mg as a single dose. 1

Immediate Treatment Protocol

First-Line Bronchodilator Therapy

• Administer salbutamol via metered-dose inhaler with large volume spacer: give one puff every few seconds until improvement occurs (maximum 20 puffs), which may be as effective as nebulized therapy 1
• Alternatively, use nebulized salbutamol 5 mg or terbutaline 10 mg via oxygen-driven nebulizer if available 1
• The expiratory wheezing after dog exposure in a patient with known asthma history represents an acute exacerbation triggered by allergen exposure 1

Systemic Corticosteroids

• Give prednisolone 30-60 mg orally immediately as a single dose 1
• Continue prednisolone 1-2 mg/kg daily (maximum 40 mg) for up to 5 days if symptoms persist 1
• Systemic steroids are essential even for moderate exacerbations to prevent progression and reduce inflammation 1

Oxygen Therapy

• Administer high-flow oxygen via face mask if available, as oxygen is of benefit during acute exacerbations 1

Assessment of Severity

Document Key Clinical Features

• Record the presence of expiratory wheeze in clinical notes, as this is a cardinal sign of asthma 1
• Measure peak expiratory flow (PEF) if possible: values ≤50% of predicted or patient's best indicate severe attack requiring more aggressive management 1
• Assess for features of severe asthma: inability to complete sentences, respiratory rate, use of accessory muscles 1

Critical Warning Signs

• Never administer sedatives or benzodiazepines during an acute asthma exacerbation, as this dramatically increases mortality risk 2, 3
• This is particularly important given the patient's concurrent risperidone therapy, which may have sedating properties 2

Drug Interaction Considerations

Bupropion and Risperidone

• Bupropion can lower seizure threshold but does not directly contraindicate standard asthma therapy [@general medical knowledge]
• Risperidone's sedating effects make vigilant monitoring essential during acute exacerbations 2
• Neither medication requires dose adjustment for acute asthma treatment, but avoid adding any additional sedating medications 2, 3

Allergen-Specific Management

Immediate Allergen Avoidance

• Remove the patient from dog exposure immediately [@1@, 1]
• Dog allergen exposure in sensitized asthmatics is associated with worsened symptoms, increased eosinophil counts, and higher bronchial hyperresponsiveness [@12@]
• Among dog-sensitized asthmatics exposed to elevated dog allergen levels, 44.2% of asthma attacks are attributable to this exposure [@11@]

Long-Term Allergen Strategy

• Strongly recommend permanent removal of the dog from the home environment, as living with a dog aggravates symptoms and biomarkers of airway inflammation in sensitized asthmatics [@12@]
• If the patient refuses pet removal, consider referral to allergist-immunologist for allergen testing and potential immunotherapy [@3@]
• Allergen-specific immunotherapy can reduce asthma symptoms and medication requirements in pet-allergic patients [@10@]

Optimization of Controller Therapy

Inhaled Corticosteroids as Foundation

• Initiate or increase inhaled corticosteroid (ICS) therapy immediately as the foundation of asthma management [@2@, @9@]
• For patients requiring frequent beta-agonist use (>2 days/week), regular anti-inflammatory treatment with ICS is mandatory 1, 3
• This will reduce future exacerbations and decrease reliance on rescue bronchodilators [@9@]

Step-Up Therapy Options

• Consider adding long-acting beta-agonist (LABA) to ICS for moderate-to-severe persistent asthma, which achieves better control than doubling ICS dose alone 1, 3
• Leukotriene receptor antagonists may be particularly appropriate given concurrent allergic rhinitis symptoms and pet allergy [@7@, @10@]
• These agents provide asthma control without beta-agonist side effects that may interact with the patient's psychiatric medications [@9@]

Follow-Up and Monitoring

Short-Term Assessment

• Reassess peak flow 30 minutes after initial bronchodilator treatment [@5@]
• If no improvement or PEF remains ≤50% predicted, arrange immediate hospital evaluation 1
• Schedule follow-up within 1-2 days to ensure resolution and optimize controller therapy [@2@]

Long-Term Management

• Evaluate for allergic rhinitis, which is present in 10-40% of asthmatics and may worsen asthma control 1
• Consider allergy testing for perennial indoor allergens including dog dander in this patient with persistent asthma requiring daily medications [@2@, @3@]
• Review inhaler technique at every visit, as proper technique is essential for adequate drug delivery [@9@]

Common Pitfalls to Avoid

• Do not delay systemic corticosteroids waiting to see if bronchodilators alone will suffice [1, @5@]
• Do not prescribe benzodiazepines for anxiety without first optimizing asthma controller therapy, as symptoms may resolve with better asthma control [@9@]
• Do not continue escalating beta-agonist doses without addressing underlying inflammation with ICS [@9@]
• Avoid recommending the patient keep the dog with "better cleaning" or air filtration, as adequate allergen avoidance is difficult to achieve and patient noncompliance is common [@10@, @12