Objective To assess whether loss of energy and concentration difficulty are related to allergic rhinitis. Design A cross-sectional study. Setting Secondary care allergy outpatients. Participants A total of 100 patients with allergic rhinitis and 96 healthy subjects. Main Outcome Measure: Loss of energy and concentration difficulty were assessed through a survey using the Beck Depression Inventory-II (BDI-II). Results The average BDI-II score was higher in the allergic rhinitis population than in the healthy controls (12.8 points vs 1.8 points, P < .0001), and the frequencies of loss of energy (69.0% vs 32.3%) and concentration difficulty (65.0% vs 34.4%) were higher in patients with allergic rhinitis ( P < .0001). The prevalence of depression was 0% in the control group and 38% in the case group ( P < .0001). Allergic rhinitis and depression were independently associated with loss of energy, odds ratio (OR) = 2.55, P = .005, and OR = 9.61, P = .001, respectively, and concentration difficulty (OR = 2.04, P = .033; OR = 6.19, P = .001, respectively). Conclusions This study is one of the first studies in Latin America to report an independent association of allergic rhinitis with loss of energy and concentration difficulty.