Evaluating the effects of standardized hydroalcoholic extract of oat grains (Avena sativa L.) capsules as an adjunctive treatment on allergic rhinitis.

Objective: L. (oat) belongs to the Poaceae family and has antihistamine, anti-inflammatory, and antioxidant effects. The aim of this study was to evaluate the effects of standardized hydroalcoholic extract of oat grains capsules as an adjunctive treatment on allergic rhinitis. Materials and methods: Hard gelatin capsules of the dried extract of oat grains were prepared, and characterized for key physico-chemical properties. Patients diagnosed with allergic rhinitis were recruited for the clinical trial to assess the effectiveness of these capsules, and were randomly divided into treatment and control groups. The participating subjects received one oat extract or placebo capsule twice daily for two weeks. All the subjects (in the control and treatment groups) also received oral antihistamines and glucocorticoid nasal spray as the standard treatment. The patients' total nasal symptom scores and the presence of allergic rhinitis symptoms were recorded at the baseline and at the end of the second week. Results: After two weeks of intervention, the patients' total nasal symptom scores and the prevalence of allergic rhinitis symptoms significantly decreased in all of them. However, supplementation with oat grain extract capsules was associated with significantly higher improvements in the outcomes in the treatment group compared with the control group. Conclusion: L.) capsules was an effective adjunctive therapy to improve allergic rhinitis symptoms.