Antihistamines Antihistamines with Decongestants Nasal Steroids Mast Cell Inhibitors Ipratropium Bromide Immunotherapy Causes and Risk Factors Allergic rhinitis results from the combination of a predisposition to develop allergy and exposure of the pre-disposed person to an allergen. Allergens are typically microscopic airborne particles such as pollen, mold spores, animal dander and dust mites. In people who are predisposed to allergy, the body reacts strongly to allergens, producing the symptoms of rhinitis.
Several factors affect the frequency and severity of the disorder s occurrence.
A patient s environment is the most important. A person who spends a lot of time outdoors, with animals, or works at a job where irritants such as dust or chemical fumes are prevalent will develop symptoms far more frequently. Repeated exposure to one allergen also makes it more likely for a person to react to another allergen. One study showed that in patients sensitized to several pollens, repeated exposure to one type of pollen caused the nasal mucosa to react to a lower dose of a second type. This sensitization means that as the pollen season progresses, less allergen is needed to produce a response, and thus patients are likely to suffer from symptoms almost constantly.