Allergic rhinitis, or hay fever, is an IgE-mediated disorder (type I hypersensitivity reaction) resulting from contact with airborne antigens (e.g. pollen, animal dander, and dust mites). The binding of allergens to specific IgE antibodies bound to the FcεRI receptor on the surface of the mast cell induces degranulation and release of mainly histamine and leukotrienes. Histamine stimulates nerve endings of sensory fibers in the nasal mucosa, which conduct the signal to the sneezing centre and the vasomotor/secretion centre. This results in symptoms such as sneezing, itchy nose, watery rhinorrhoea, nasal blockage, and ocular symptoms.
Avoidance of exposure to allergens is simple and effective in reducing symptoms. When this is not achievable, drug treatment with antihistamines, corticosteroids or cromolyn sodium can be used. For general information on the treatment see drugs for allergic rhinitis.
All of the following are appropriate suggestions for a pharmacist to give to a patient with allergic rhinitis from multiple environmental triggers, to minimize exposure to possible allergens, EXCEPT: