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Updated: Aug 10, 2026

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber
Published on: March 3, 2023
Loratadine/pseudoephedrine for nasal symptoms in seasonal allergic rhinitis: a double-blind, placebo-controlled study
1Allergy Clinic, University of Chicago Medical Center, IL, USA.
Abstract:
In this double-blind, placebo-controlled, crossover, parallel study, we treated 20 adults who had seasonal allergic rhinitis with once-daily fixed-combination loratadine/pseudoephedrine sulfate to observe its effect on relieving symptoms, primarily nasal congestion. Acoustic rhinometry detected a trend toward improvement in nasal patency, although the difference between pre- and post-treatment measures was not statistically significant. Endoscopic inferior turbinate photography documented that treatment led to statistically significant reductions in the amount of nasal edema and nasal secretions. The results of a quality-of-life questionnaire suggested that treatment alleviated nasal and ocular symptoms of rhinoconjunctivitis. An analysis of subjective visual analog scale scores showed a trend toward improvement in most but not all nasal symptoms. We conclude that once-a-day fixed-combination loratadine/pseudoephedrine is effective in relieving nasal congestion in patients with seasonal allergic rhinitis.
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