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Updated: Aug 17, 2026

Symptom Assessment of Patients with Allergic Rhinitis Using an Allergen Exposure Chamber
Published on: March 3, 2023
Treatment of allergic rhinitis with a new selective H1 antihistamine: terfenadine
Abstract:
The effectiveness of 60 mg b.i.d. of a novel antihistamine, terfenadine, was compared with an active control, 4 mg t.i.d. of chlorpheniramine, and placebo in 560 patients with seasonal allergic rhinitis. In contrast to the gradual decrease in seasonal symptoms observed over a 7 day period of study in placebo-treated patients, both antihistamines produced a prompt significant decrease in sneezing and rhinorrhea, and a gradual decrease in nasopharyngeal pruritus. Terfenadine-related sedation did not differ from that produced by the placebo and was less than the sedation produced by the active control.
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