In recent years, there has been an increased clinical use of indigenous drugs due to side effects and expenses associated with allopathic drugs. Indian herb Eclipta prostrata is a traditional medicinal plant, known for its anti fungal, anti bacterial and anti hapatitic properties. The present investigation aims at evaluating the immunomodulating properties of ethanol and aqueous extracts of leaves of E. prostrata. Swiss albino female mice (40 to 60 g) were used as animal model. The ethanol and aqueous extracts of E. prostrata were pretreated orally for 45 days at a dose of 150 to 300 mg/Kg/b.wt. The effect of herbal extracts on body weight was monitored and a significant increase was noticed in ethanol extract than aqueous. After the post treatment of herbal extract for 45 days, animals in all test groups including control were immunized with Sheep Red Blood Cell by i.p. route. Twenty-four hours after immunization, various immunological assays, such as neutrophil adhesion, delayed type hypersensitivity and haemagglutination reaction were performed to evaluate humeral and cell mediated immune response. No significant response was noticed in aqueous extract at both 150 and 300 mg/Kg. The ethanol extract showed a dose dependent increase in the entire test performed against SRBC at the concentration of 150 to 300 mg/Kg b.wt. Moreover, the ethanol extract showed very good response in the enhanced antibody production and diminished DTH activity. Hence, the ethanol extract has a strong potential immunostimulant activity, particularly humoral response, against SRBC; although it could be explored further as an immune-based ayurvedic therapy. 

Key words: Eclipta prostrata, immunostimulant, hypersensitivity reaction, hemagglutination.