Understanding the multi-herbal composition of Buyang Huanwu Decoction: A review for better clinical use.

ETHNOPHARMACOLOGICAL RELEVANCE: Buyang Huanwu Decoction (BHD) is a multi-herbal composition commonly prescribed in the treatment of cerebrovascular diseases such as stroke. Although studies have been conducted at the cellular (in vitro), animal and human (in vivo) level, there was no detailed analysis on how the composition and proportion of BHD is modified according to target diseases. AIM OF STUDY: The purpose of this study is to investigate the composition and proportion of each herb in BHD to summarize how the original BHD was modified according to the target disease. MATERIALS AND METHODS: Electronic literature searches were performed in three databases, collecting sixty-eight studies for the final analysis. The studies were divided into three types: cell studies, animal experiments and clinical trial. In the analysis, the decoction formula including the composition and the weight proportion of the herbs in BHD used in the studies and the target diseases were examined. RESULTS: The result showed that in cell studies, the targets were mostly cell differentiation, cell injury and immune activation. In animal studies, cerebrovascular diseases such as cerebral ischemia were the most identified target diseases followed by nervous system and cardiovascular diseases. While the proportions of the herbs in BHD used in these studies were in general similar to the original formula, some studies reduced the amount of Astragali Radix to half of the original amount. Modified BHDs were used in four studies for cerebrovascular and peripheral nerve diseases. However, no significant correlation has been observed between the target diseases and the change of the proportion of the herbs in BHD. CONCLUSIONS: The most commonly used formula was the original composition of BHD, and modified BHDs were reported to be used to treat cerebrovascular and nervous diseases. Further studies about the effects of BHD by composition and proportion of herbs are needed in the future.