antitussive effect of plantago lanceolata in guinea pigs

background: several therapeutic effects including anti-asthma and dyspnea have been described for plantago lanceolata . in the present study the antitussive effect of this plant was evaluated.   methods: the antitussive effects of aerosols of two different concentrations of soxhlet and macerated ethanolic extracts, codeine and saline were tested by counting the number of coughs produced due to aerosol of citric acid 10 min after exposing the animal to aerosols of different solutions (n=8 for each solution).   results: the results showed significant reductions of cough number observed in the presence of both concentrations of soxhlet and macerated extracts of plantago lanceolata as compared to saline treated group (p<0.001). the reduced cough number observed in the presence of higher concentrations of extracts was not significantly different from that of lower concentrations of lp. furthermore, there was no significant difference between the cough numbers observed in the presence of both concentrations of the extracts with that of codeine.   conclusion: the ethanolic extracts of plantago lanceolata have antitussive effects comparable with that of codeine. iran j med sci 2006; 31(3): 143-146.   keywords ● plantago lanceolata ● antitussive effect ● guinea pig ● citric acid ● codeine