In Oriental medicine, the prescriptions composed of several herb medicines have been used. It is still unclear how the sum of several extracts of anti-thirst drugs represents the anti-lipid peroxidative action. Three anti-thirst herb medicines, Kalopanax pictus (K), Pueraria thunbergiana (P) and Rhus verniciflua (R), were extracted with MeOH and $H_2O$, respectively, and the former one was fractionated into the resultant EtOAc extract. Each extract was reconstituted to give KPR311, KPR131 and KPR113 where, for example, KPR311 represents the complex of K-P-R {3:1:1 (w/w/w)} of the three extracts. The order of the inhibitory effect in bromobenzene-induced lipid peroxidation in rats was as follows: EtOAc extract＞$H_2O$ extract＞MeOH extract. Extract complexes were found to be more potent than the extracts of individual crude drugs. The KPR131 of EtOAc extract was found to be the most potent among the tested samples. These anti-lipid peroxidative effects were also supported by the decrease of aniline hydroxylase activity and aminopyrine N-demethylase activity, on the other hand by the increase of epoxide hydrolase activity. All the tested samples were assayed in vitro antioxidative effects such as DPPH assay, ADP/NADPH/Fe$^{3+}$ assay and ascorbic acid/Fe$^{2+}$ assay. The EtOAc extracts also showed the most significant antioxidative effects. These results suggest that the sum of anti-thirst drugs could reflect the effects of respective crude drugs.s.s.