Allergic rhinitis is an uncommon disease of cattle that, when chronic, may lead to granuloma formation. The etiology is an allergic reaction to pollen or fungal spores. Signs are seasonal and occur under warm, moist conditions; they include rhinorrhea, sneezing, and a sudden onset of dyspnea. In the chronic stage, multiple granulomas may form on the mucosal surface of the nasal cavity. Cytologic examination of nasal discharges may reveal eosinophils. Treatment should focus on removing the allergen or removing the animal from the allergen. Treatment with corticosteroids to block the hypersensitivity reaction is a consideration.