Antinociceptive activity was evaluated by abdominal writhing and tail flick methods in Swiss albino mice. Acetyl salicylic acid was used as standard drug.
A dose dependent significant (P<0.01) antinociceptive activity was observed in three different concentrations 100, 200 and 300 mg/kg. Among them dose at 300 mg/kg, significantly (P<0.01) inhibited (74.94 % ) the nociception induced by acetic acid but less effective than the standard reference (84.06 % ). Tail-flick test showed that the extract at the doses 300 mg/kg showed efficient results when compared to the other two doses (100 and 200 mg/kg) with increase in the latency to response of tail to the thermal stimulation.
The significant antinociceptive activity of the leaf extract is due to the presence of a single active constituent in higher levels or due to the combined effect of more than one phytoconstituent. This investigation supported the ethnomedicinal claims of Delonix elata.