Abstract: Objective To summarize the current studies on processing methods to decrease toxicity of toxic herbal TCM in China so as to provide reference for subsequent studies. Methods Toxicity-decreasing processing methods and similarities and differences between these methods when used in a variety of medicinal parts were analyzed via literature review. Results The commonly used processing methods for toxic Chinese herbal medicines included JingZhiFa, ChaoZhiFa, FuLiaoGongZhiFa, QuYouZhiShuangFa. Medicinal parts could be divided into three parts: root and rhizome drugs, fruit and seed drugs and resin drugs. Processing methods varied depending on the medicinal parts. For example, steaming and boiling were used for root and rhizome drugs, while oil removal was employed to reduce toxicity in fruit and seed drugs rich in oil. Conclusion The main objective of processing for toxicity reduction is to remove toxic components and reduce adverse reactions of drugs. However, the toxicity and active components of most of the toxic Chinese herbal medicines are not clear, throwing doubt on the feasibility of these processing methods. The mechanism by which toxicity is minimized should be clarified, processing conditions should be optimized, and the relationships between toxicity and efficacy should be balanced.

Key words: herbal traditional Chinese medicine, toxicity-decreasing processing method, processing mechanism, toxicity