Supplementary Material for: Efficacy and safety of phytotherapy and anthroposophic medicine in seasonal allergic rhinitis: A systematic review

Introduction: Seasonal allergic rhinitis (SAR) is a common health condition that is associated with an increased risk for bronchial asthma. Besides conventional medicine, treatments from traditional, complementary and integrative medicine (TCIM) are widely used by individuals with SAR. This review aims to systematically summarize evidence on the efficacy, effectiveness and safety of European/Western phytotherapy (PT) and medications from anthroposophic medicine (AM) in individuals with SAR. Methods: Four electronic databases were screened for clinical studies published between January 1990 and March 2023. The results were qualitatively synthesized and the study quality was assessed. Results: In total, 14 studies were included, eleven from European/Western PT and three from AM. About half of the studies were rated as being of sufficient quality. The most frequently studied plant was Petasites hybridus (butterbur), showing beneficial effects on immunological parameters, subjective symptoms and nasal airflow. Beneficial immunological and clinical effects were also shown for an herbal preparation combining Citrus limonis (lemon) and Cydonia oblonga (quince). The medications examined by studies of sufficient quality were judged to be safe. Conclusion: In summary, this systematic review highlights two herbal preparations, one from European/Western PT and one from AM, that appear to be promising options in the treatment of SAR.