Objective:To screen the optimal compositions for the anti-chronic bronchitis activity from components of Aster ageratoides. Method: ① Seventy-two Kuenming mice were randomly divided into the normal group

ammonium chloride group(0.1 g·kg-1) and groups of different proportions of total saponins and total flavonoids(Setting 8∶1

4∶1

2∶1

1∶1

1∶2

1∶4

1∶8 of total saponins and total flavonoids with increase-decrease baseline geometric proportion design method). Every group was ig administrated at dose of 1.0 g·kg-1 once a day for 3 days.The effect of eliminating phlegm detected by the quantity of phenolsulfonphthalein excretion was taken as the indicators for the optimization of compositions. ② Seventy-two mice were randomly divided into groups as ditto. The positive control group was administrated carbetapentane at dose of 0.04 g·kg-1. The effect of stopping coughing against ammonia water stronger was taken as the indicators for the optimization of compositions. Result: ①For the same total dosage

compared with blank group

the eliminating phlegm effects of group 8∶1(total saponins∶total flavonoids)

group 4∶1

group 2∶1

group 1∶1

group 1∶2

group 1∶4 and group 1∶8 were increasing with the proportion of total saponins increased

and vice versa(P<0.05 or P<0.01)

but the eliminating phlegm effects of all group were not as good as ammonium chloride. ②Compared with blank group

the cough frequency in 2 minutes were decreased and latency period were extended significantly for all groups(P<0.05 or P<0.01)

especially for group 1∶1 (25.11±4.20) frequency(f) per a time.(2 min)

(60.44±10.31) s and group 1∶2(22.13±7.02) f per a time (2 min)

(66.50±6.6) s

(P<0.01). The effects of decreasing cough frequency in 2 minutes of group 1∶2 and the carbetapentane group(20.78±8.17) f per a time.(2 min) had no significant difference. Conclusion: For the same total dosage

the eliminating phlegm effects of different proportions of total saponins and total flavonoids of A. ageratoides showed dose-dependent; the inbiting cough effects of group 1∶1 and group 1∶2 not only depend on total flavonoids

but on synergetic compatibility relationship between total saponins and total flavonoids. The optimal composition of flavonoids and total saponins of A. ageratoides would still need further study through other pharmacodynamic action and toxicity from chemical reaction

absorption and metabolism between different components.