Allergic rhinitis is a chronic inflammatory disease of the upper airways.1-4 It is characterized by one or more of the following symptoms: nasal congestion, rhinorrhea, sneezing, and itching. This disease affects 10% to 30% of all adults and up to 40% of children.2 In the United States, allergic rhinitis affects nearly 50 million people. Allergic rhinitis can significantly impact quality of life. Subjects who suffer from this disorder complain of missed work and schooldays and sleep disturbance.
Allergic reactions in the nose are mediated by immunoglobulin E (IgE).5 In patients with allergic rhinitis, airborne allergens react with antigen-specific IgE bound to mast cells, thereby triggering release of inflammatory mediators such as histamine and leukotrienes. Both early (immediate) and late-phase allergic reactions occur following allergen exposure. The early-phase reaction happens within seconds to minutes and is mainly due to the release of histamine, leukotrienes, tryptase, and cytokines. Sneezing, itching, rhinorrhea, and congestion are typical symptoms. The release of cytokines results in the infiltration of inflammatory cells such as basophils and eosinophils. This produces a late-phase reaction that usually occurs 4 to 8 hours after allergen exposure. With continued exposure to the allergen, the late-phase inflammatory response results in chronic symptoms of allergic rhinitis.
Patients with allergic rhinitis may present with the following symptoms: clear rhinorrhea, nasal congestion, allergic conjunctivitis, sneezing, postnasal drip, and itchiness in the nose, ears, and/or eyes.1 Allergic shiners (swelling and darkening of circles under the eyes due to nasal obstruction and venous congestion) and allergic salute (upward rubbing of the nose) are less reported signs.
Allergic rhinitis can be differentiated from other types of rhinitis by a thorough history and physical examination. Chief concerns, symptoms, patterns, and triggers of nasal and related symptoms should be obtained from the patient. Percutaneous skin testing or allergen-specific IgE antibody testing (eg, radioallergosorbent test [RAST]) are the most common tests used to confirm the diagnosis of allergic rhinitis.
Two classification schemes exist to grade the severity of allergic rhinitis. The Allergic Rhinitis and its Impact on Asthma (ARIA) organization has designated four categories of allergic rhinitis: mild intermittent, mild persistent, moderate-severe intermittent, and moderate-severe persistent.6 Patients who experience symptoms <4 d/wk or for less than 4 consecutive weeks meet the criteria for intermittent allergic rhinitis. The persistent classification applies to patients whose allergic rhinitis symptoms occur more than 4 d/wk and for more than 4 consecutive weeks. If symptoms do not impact daily activities, sleep patterns, work, or school, then the disease is considered mild. If these areas are impacted by allergic rhinitis, then the patient has a moderate-severe form. In a second classification scheme, the Joint Task Force on Practice Parameters categorizes allergic rhinitis as seasonal, perennial, or episodic.2Seasonal allergic rhinitis refers to those patients with symptoms primarily during the spring and fall (high pollen seasons). Patients with perennial allergic rhinitis have symptoms throughout the year. Patients with episodic allergic rhinitis experience symptoms by sporadic exposures ...