Allergic rhinitis is a chronic condition that affects 10% to 25% of the population,1 with a significant impact on patients’ lives, especially the quality of sleep.2 The allergic patient is characterized by emotional instability, sometimes called the “allergic irritability syndrome,”3 and increased anxiety.4,5 Stress has also been shown to increase morbidity in children with asthma.6 Allergic rhinitis involves the activation of nasal mast cells,7 which are now considered important in immuni- ty,8 especially on mucosal surfaces.9 Mast cells are also implicated in nervous-immune interactions10 and in the patho- genesis of inflammatory conditions worsened by stress.11 We hypothesized that nasal mast cell stimulation by allergens may release molecules that could activate the hypothalamic- pituitary-adrenal (HPA) axis. These molecules could include corticotropin-releasing hormone (CRH),12 histamine,13 interleukin 1 (IL-1),14 IL-6,15 and prostaglandins.16,17 The HPA axis may then become overactive, leading to unwanted be- havioral and physical consequences.
