These showed that these alkaloids shared low plasma concentration. Previous studies concluded that the poor absorption and extensive metabolism might result in low plasma concentration of berberine after oral administration [23]. Because of their similar structures with berberine and lower contents for administration, the plasma concentration of the other four protoberberine-type alkaloids was lower. The values of T1/2 were in the range of 0.28–12.4 h, which were greatly different from previous study [23]. This was probably due to the different proportions of the components in JJT tablet and the individual differences in rats