Nonallergic Rhinitis

Abstract

Rhinitis is defined as the inflammation of the nose. Its major symptoms are nasal congestion, rhinorrhea and sneezing. It is a common clinical disorder that causes substantial morbidity universally. It is well known that it has a negative influence on life quality, and functioning at the office and the classrooms. Although rhinitis is a universal disease, it is associated with many controversies, including its definitions, classifications, and terminology. Since there is high variability in both underlying pathophysiologic mechanisms (endotypes) and clinical presentations (phenotypes) of rhinitis, no clear guidelines for its diagnosis and treatment have been established. Even the term “rhinitis” is controversial since it implies inflammation; however, some rhinitis phenotypes seem to lack an inflammatory component. Nonallergic rhinitis is a heterogeneous collection of nasal conditions characterized by symptoms like rhinorrhea, nasal congestion, sneezing, and postnasal drainage not related to IgE-mediated events. The practicing otolaryngologist should take into account a broad differential of potential rhinitis types whilst bearing in mind the diagnosis of chronic rhinitis, along with the following subtypes of nonallergic rhinitis which include nonallergic rhinopathy, formerly referred to as vasomotor rhinitis or idiopathic rhinitis, nonallergic rhinitis with eosinophilia syndrome (NARES), drug-induced rhinitis, hormonal-induced rhinitis, atrophic rhinitis, senile rhinitis, gustatory rhinitis, and chronic rhinosinusitis. This chapter focuses on the poorly comprehended condition called nonallergic rhinitis and helps the reader on determining the pathophysiology, differential diagnosis, and treatment of its subtypes.