Allergic rhinitis and asthma are both chronic heterogeneous disorders, with an overlapping epidemiology of prevalence, health care costs and social costs in quality of life. Both are inflammatory disorders with a similar pathophysiology, and both share some treatment approaches. However, each disorder has an array of treatments used separately in controlling these atopic disorders, from inhaled corticosteroids, beta2-agonists and antihistamines to newer monoclonal antibody-based treatments. Allergic rhinitis is a common disorder that is strongly linked to asthma and conjunctivitis. It is usually a long-standing condition that often goes undetected in the primary-care setting. The classic symptoms of the disorder are nasal congestion, nasal itch, rhinorrhea and sneezing. A thorough history, physical examination and allergen skin testing are important for establishing the diagnosis of allergic rhinitis.
Dysfunction of the upper and lower airways frequently coexist, and they appear to share key elements of pathogenesis. Data from epidemiologic studies indicate that nasal symptoms are experienced by as many as 78% of patients with asthma and that asthma is experienced by as many as 38% of patients with allergic rhinitis. Studies also have identified a temporal relation between the onset of rhinitis and asthma, with rhinitis frequently preceding the development of asthma. Patients with allergic rhinitis and no clinical evidence of asthma commonly exhibit nonspecific bronchial hyperresponsiveness. The observation that management of allergic rhinitis also relieves symptoms of asthma has heightened interest in the link between these diseases. The observation that management of allergic rhinitis also relieves symptoms of asthma has heightened interest in the link between these diseases. Intranasal corticosteroids can prevent increases in nonspecific bronchial reactivity and asthma symptoms associated with seasonal pollen exposure. Similarly, among patients with perennial rhinitis, daily asthma symptoms, exercise-induced bronchospasm, and bronchial responsiveness to methacholine are reduced after administration of intranasal corticosteroids. Antihistamines, with or without decongestants, reduce seasonal rhinitis symptoms, asthma symptoms, and objective measurements of pulmonary function among patients with rhinitis and asthma.