Anthroposophic medications (AMED) are prescribed by physicians in 56 countries worldwide and are used for the treatment of a variety of conditions. However, safety data on long-term use of AMED from large prospective studies are sparse. The objective of this analysis was to determine the frequency of patient-reported and physician-assessed adverse drug reactions (ADRs) to AMED in outpatients using AMED for chronic diseases over a 2-year period.We conducted a prospective observational cohort study involving 131 medical practices in Germany. In total, 662 consecutive outpatients aged 1-75 years were enrolled in the study. The patients were using AMED for mental (primarily depression and fatigue), musculoskeletal, respiratory, neurological and other chronic diseases. Main outcome measures were use of AMED and ADRs to AMED.Throughout the 2-year follow-up, patients used 949 different AMED for a total of 11 487 patient-months. The origin of AMED was mineral (8.1%, 77 of 949 AMED), botanical (41.8%), zoological (7.8%), chemically defined (10.5%) and mixed (31.7%). Most frequently used AMED ingredients were Viscum album (11.5%, 76 of 662 patients), Bryophyllum (9.4%), Arnica (7.9%) and Silicea (7.7%). Non-AMED products were used by 94.2% of patients for a total of 11 202 patient-months; 45.2% of this use was accounted for by medication for the CNS, the cardiovascular system and the alimentary tract and metabolism. A total of 1861 adverse events (AEs) were documented. The most frequent AEs were non-specific symptoms, signs and findings (International Classification of Diseases [10th Edition] R00-R99: 27.6%, 513 of 1861 AEs), musculoskeletal (M00-M99: 16.9%), respiratory (J00-J99: 8.2%) and digestive diseases (K00-K93: 6.6%). No serious AEs attributable to any medication occurred. Out of the 1861 reported AEs, 284 (15.3%) AEs were suspected by the physician or the patient to be an adverse reaction to non-medication therapy (n = 42 AEs), non-AMED (n = 187) or AMED (n = 55 AEs in 29 patients). Twenty of these 29 patients had confirmed ADRs to 21 AMED. These ADRs were local reactions to topical application (n = 6 patients), systemic hypersensitivity (n = 1) and aggravation of pre-existing symptoms (n = 13). In ten patients, AMED was stopped due to ADRs; two patients had ADRs of severe intensity. Median number of days with ADRs was 7 (range 1-39 days). All ADRs subsided, none were serious. The frequency of confirmed ADRs to AMED was 2.2% (21 of 949) of all different AMED used, 3.0% (20 of 662) of AMED users and one ADR per 382 patient-months of AMED use.In this 2-year prospective study, AMED therapy was generally well tolerated.
