Antitussive effect of nigellla sativa in guinea pigs

ABSTRACT

Several therapeutic effects including anti-asthma and dyspnea have been described for the seeds of Nigella sativa. In previous studies the relaxant and anticholinergic [functional antagonism] effects, histamine H, inhibitory effect, and calcium channel blocking effect of Nigella sativa have been demonstrated on guinea pig tracheal chains. In the present study the antitussive effect of this plant was evaluated. The antitussive effects of aerosols of two different concentrations of aqueous and macerated extracts, one concentration of boiled extract, codeine, and saline were tested by counting the number of coughs produced due to aerosol of citric acid 10 min after exposing animal to aerosols of different solutions [n=7 for each solution]. The results showed significant reduction of cough number observed in the presence of both concentrations of aqueous and macerated extracts, boiled extract and codeine [p<0.05 to p<0.001]. The cough number observed over a period of five minutes in the presence of higher concentrations of aqueous and macerated extracts were also significantly less than those of lower concentrations [p<0.05 for aqueous and p<0.01 for macerated extracts]. In addition there was not any significant difference between cough numbers observed in the presence of all extracts with that of codeine. These results indicated an antitussive effect of Nigella sativa, which was comparable to that of codeine