RESUMEN
Everted intestinal sac models were used to investigate the intestinal absorption of the 4 alkaloids(berberine, palmatine, coptisine, and epiberberine) in Fuzheng Xiaozheng Fang(FZ) at different intestine segments. The absorption parameters of each component were calculated; SPSS 20.0 software was used to analyze the data and evaluate the absorption characteristics at different intestinal segments. The results showed that all the four active ingredients conformed to zero-order absorption rate. There was significant difference in absorption rate constant (Ka) between the four ingredients at low dose and medium and high dose groups(P<0.05), but there was no significant difference in Ka between medium dose and high dose. The absorption mechanization of four ingredients presented two absorption manners： positive diffusion and passive absorption. The absorptive amount of 4 alkaloids in ileum was slightly greater than that of jejunum, but no significant differences were observed, which indicated that these four alkaloids had no specific absorption windows in intestinal segment.