Small and Kim Allergy, Asthma & Clinical Immunology 2011, 7(Suppl 1):S3 http://www.aacijournal.com/content/7/S1/S3 Page 5 of 8 Allergen avoidance Oral antihistamines Intranasal corticosteroids Leukotriene receptor antagonists Allergen immunotherapy Figure 2 A simplified, stepwise algorithm for the treatment of allergic rhinitis.Note: Treatments can be used individually or in any combination. compliance with this recommendation is poor and, therefore, the use of high-efficiency particulate air (HEPA) filters and restricting the animal from the bed- room or to the outdoors may be needed to attempt to decrease allergen levels. Measures for reducing exposure to mould allergens include cleaning with fungicides, dehumidification to less than 50%, and HEPA filtration. These avoidance strategies can effectively improve the symptoms of allergic rhinitis, and patients should be advised to use a combination of measures for optimal results [1]. Antihistamines The newer, non-sedating, second-generation oral anti- histamines (e.g., desloratadine [Aerius], fexofenadine [Allegra] and loratadine [Claritin]) are the first-line pharmacological treatments recommended for all patients with allergic rhinitis (see Table 3 for a list of second-generation antihistamines and their recom- mended dosing regimens). These agents have been found to effectively reduce sneezing, itching and rhinor- rhea when taken regularly at the time of maximal symp- toms or before exposure to an allergen. Although the older (first-generation) sedating antihistamines (e.g., diphenhydramine, chlorpheniramine) are also effective in relieving symptoms, they have been shown to negatively impact cognition and functioning and, there- fore, they are not routinely recommended for the treat- ment of allergic rhinitis [1,6]. Intranasal corticosteroids Intranasal corticosteroids are also first-line therapeutic options for patients with mild persistent or moderate/ severe symptoms and they can be used alone or in com- bination with oral antihistamines. When used regularly and correctly, intranasal corticosteroids effectively reduce inflammation of the nasal mucosa and improve mucosal pathology. Studies and meta-analyses have shown that intranasal corticosteroids are superior to antihistamines and leukotriene receptor antagonists in controlling the symptoms of allergic rhinitis, including nasal congestion, and rhinorrhea [11-14]. They have also been shown to improve ocular symptoms and reduce lower airway symptoms in patients with concurrent asthma and allergic rhinitis [15-17]. The intranasal corticosteroids available in Canada are shown in Table 3 and include fluticasone furoate (Ava- mys), beclomethasone (Beconase), fluticasone propionate (Flonase), triamcinolone acetonide (Nasacort), mometa- sone furoate (Nasonex), ciclesonide (Omnaris) and budesonide (Rhinocort). Since proper application of the nasal spray is required for optimal clinical response, patients should be counseled on the appropriate use of these intranasal devices. Ideally, intranasal corticoster- oids are best started just prior to exposure to relevant allergens and, because their peak effect may take several days to develop, they should be used regularly [4]. The most common side effects of intranasal corticos- teroids are nasal irritation and stinging. However, these side effects can usually be prevented by aiming the spray slightly away from the nasal septum [1]. Evidence suggests that intranasal beclomethasone, but not other intranasal corticosteroids, may slow growth in children compared to placebo; however, long-term studies exam- ining the impact of intranasal beclomethasone on growth are lacking [18-21]. It is important to note that most patients with allergic rhinitis presenting to their primary-care physician have moderate-to-severe symptoms and will require an intra- nasal corticosteroid. Bousquet et al. noted improved outcomes in patients with moderate-to-severe symptoms treated with a combination of these agents [22]. Leukotriene receptor antagonists The leukotriene receptor antagonists (LTRAs) montelu- kast and zafirlukast are also effective in the treatment of allergic rhinitis; however, they do not appear to be as effective as intranasal corticosteroids [23-25]. Although one short-term study found the combination of LTRAs and antihistamines to be as effective as intranasal