Author
Bernstein CK, Deng C, Shuklah R, et al.
Date
3/
Journal
American Academy of Allergy, Asthma and Immunology (AAAAI) 57th Annual Meeting.
Abstract
Despite the virtual absence of controlled clinical studies, a variety of herbal supplements are marketed as effective for treatment of SAR and asthma. Polyphenolic bioflavanoids are natural constituents of grapeseed extract, apple, tea, and quercitin (citrus and buckwheat), which possess anti-oxidant properties. Some of these compounds (e.g., epitcatechin) are touted as having anti-allergic properties. The aims of this study were twofold: 1) to determine the clinical efficacy and safety of the dietary supplement, grapeseed extract (GSE), compared to placebo for prevention of symptoms of seasonal allergic rhinitis; and 2) to adapt placebo-controlled study designs commonly used in clinical drug trials to the objective evaluation of herbal supplements for SAR. Pts. were randomly assigned to 8 wks. of treatment with either GSE (n=25) 100 mg. bid or placebo matched capsules (n=24) beginning 2-4 weeks before the onset of ragweed pollination. Patients were evaluated via daily symptom diary cards, Rhino-conjunctivitis Quality of Life Questionnaire (RQOL), global evaluations of treatment on the final visit, and requirement for rescue antihistamines. No significant differences were detected between GSE and placebo treated groups in symptom diary scores, rescue antihistamine, RQOL scores or peripheral eosinophil counts. There were no significant differences between the two treatment groups in reported adverse events. In conclusion, there was no trend supporting the efficacy of grapeseed extract in the treatment of SAR. This is a rare example in which a rigorous study design was applied to the evaluation of an herbal remedy which has been promoted as being effective in treating allergic disorders.
