Assessment of the antiobstructive effect of fexofenadine on nasal allergy challenge in patients with seasonal allergic rhinitis.

The oral administration of fexofenadine 120 mg daily is a common treatment of seasonal allergic rhinitis (SAR). It reduces the H1 receptor-mediated symptoms, such as sneezing, pruritus, and nasal secretion as well as non-nasal symptoms such as conjunctivitis. The objective was to assess the effect of fexofenadine on nasal symptoms (such as nasal obstruction) in seasonal allergic rhinitis. A placebo-controlled, double-blind, randomized, cross-over study was performed which yielded evidence that two-week therapy with fexofenadine 120 mg daily in patients with SAR also relieves nasal obstruction and congestion. The parameters of nasal obstruction were evaluated by means of rhinoscopy, a subjective symptom score, and active anterior rhinomanometry. The subjective evaluation of nasal obstruction/congestion as recorded by the patient every 15 minutes for 4.5 hours after nasal allergen provocation showed a significant difference of the AUC (p = 0.025) between fexofenadine and placebo with a 12.8% lower obstruction after fexofenadine. The swelling of the nasal mucosa, which was assessed by rhinoscopy for 4.5 hours after nasal allergen provocation, was 21% lower after treatment with fexofenadine (p = 0.041). In this double-blind, placebo-controlled trial, subjective patient ratings as well as objective investigator assessments demonstrate the anti-obstructive effect of fexofenadine in nasal allergen challenge.