ABSTRACT
<p><b>OBJECTIVE</b>To study the toxicity changes of different proportions of Radix Adenophora, Radix Glehniae combined with Veratrum nigrum L., thus providing acute toxicity data and investigating whether decoction factors were correlated with toxicity.</p><p><b>METHODS</b>The uniform design method was used by two factors and seven levels to investigate the toxicity changes in different proportions of Radix Adenophora, Radix Glehniae combined with Veratrum nigrum L. The decoction factors were also investigated.</p><p><b>RESULTS</b>The compatibility toxicity was affected mainly by Veratrum nigrum L. and the toxicity increased along with increased doses of Veratrum nigrum L. The toxicity of co-decoction was higher than mixed decoction in the same dosage of Radix Glehniae and Veratrum nigrum L. The promotion of the dissolution of the toxic component of Veratrum nigrum L. in co-decoction may be the cause of the higher toxicity.</p><p><b>CONCLUSION</b>Radix Adenophora and Radix Glehniae combined with Veratrum nigrum L. resulted in higher toxicity, which indicated that the incompatibility between Radix Adenophora, Radix Glehniae, and Veratrum nigrum L. In clinic practice, a prescription contained these drugs should be avoided.</p>