Objective: To explore whether the compatibility of Niuhuang Jiedu tablets could reduce the toxicity of realgar

and which may be the possible herbal medicines that could reduce toxicity in the Niuhuang Jiedu tablets prescription. Method: Different groups about Niuhuang Jiedu Tablets and its disassembled prescription were arranged

treated with artificial gastric juice or artificial intestine juice

and then atom fluorescence spectrophotometry (AFS) was used to detect the content of soluble arsenic in the different groups samples. Result: The content of soluble arsenic in the whole prescription was significant lower than that in the single realgar (P<0.01). The content of soluble arsenic in the whole prescription except for Gancao

Huangqin and Dahuang was significant higher than that in the whole prescription (P<0.01). Conclusions: The compatibility for Niuhuang Jiedu tablets could reduce the toxicity of realgar

and Gancao

Huangqin and Dahuang may be the possible herbal medicines that could reduce toxicity.