Pet dander and difficult-to-control asthma: Therapeutic options

The prevalence of sensitization to cat and dog allergens is high in the general population and poses a challenge to the physician managing allergic asthma. Adequate allergen avoidance is difficult to achieve because of the physical characteristics of airborne animal allergens and patient noncompliance. Allergen-specific high-dose subcutaneous immunotherapy has shown benefit in cat-allergic patients with asthma and rhinoconjunctivitis, whereas the data for dog-allergic patients are not as convincing. Alternative immunotherapy approaches including the sublingual route or allergen-derived peptide-based immunotherapy remain experimental. Pharmacotherapy of pet-allergic asthmatic patients requires a stepwise approach following established asthma management guidelines. In addition to short-acting beta-agonists and inhaled corticosteroids, prophylactic antihistamines before anticipated pet exposure, the use of intranasal steroids, and the use of leukotriene antagonists may also be considered as adjunctive therapy in pet-allergic patients with asthma and/or allergic rhinitis. Omalizumab appears to have particular efficacy in pet allergen-induced asthma. Novel therapies such as Fcgamma-Fel d 1 chimeric proteins still have to be evaluated in the human setting.