Treatment for seasonal allergic rhinitis by Chinese herbal medicine : a randomized placebo controlled trial

Context: Chinese herbal medicine (CHM) is widely used to treat seasonal allergic rhinitis (SAR), however, evidence of efficacy is lacking. Objective: To evaluate the efficacy of a Chinese herbal formulation for the treatment of SAR. Design: Randomized, double blind, placebo controlled trial. Setting: RMIT Chinese Medicine Clinic, Patients: 55 patients with seasonal allergic rhinitis (active 28, placebo 27). Interventions: CHM extract capsule (containing 18 herbs) or placebo, given daily for 8 weeks. Main Outcome Measures: The primary measure of efficacy were changes in severity of nasal and non-nasal symptoms using a Five Point Scale (FPS) measured by both patients and the practitioner. The secondary measure was the change in score for the domains measured in the Rhinoconjunctivitis and Rhinitis Quality of Life Questionnaire (RQLQ) assessed by patients. Results: Forty-nine patients completed the study (active 24, placebo 25). After eight weeks, the severity of nasal symptoms and non-nasal symptoms were significantly less in the active treatment group than in the control group, both for measurements made by patients and those by the practitioner. Comparison of active and placebo treatment groups RQLQ scores also indicated significant beneficial effects of treatment (end point Section 1: P<0.05; Section 2: P<0.01). Intention-to-treat analyses of categorical items showed moderate to marked improvement rates were 60.7% and 29.6% for active and placebo respectively. Eleven patients reported mild adverse events including 1 withdrawn from the trial. Conclusions: This CHM formulation appears to offer symptomatic relief and improvement of quality of life for some patients with seasonal allergic rhinitis.