Evaluation of Analgesic and Neuropharmacological Activities of Methanolic Rhizome Extract of Hedychium Coronarium

This study was aimed to investigate analgesic and neuropharmacological actions of the methanolic extract of rhizomes of Hedychium coronarium. The analgesic activity was evaluated for its central and peripheral pharmacological actions using tail immersion method and acetic acid-induced writhing test in mice respectively. The extract, at the doses of 100, 200 and 400 mg/kg body weight, produced a significant increase in pain threshold in tail immersion methods in a dose dependent manner. In acetic acid-induced writhing test, the extract at 400 mg/kg dose showed a maximum of 73.12% writhing inhibition (p <0.001) compared to the control and this activity was comparable to 75.78% inhibition of writhing by standard drug Diclofenac-Na (25 mg/kg). The extract was also investigated for its neuropharmacological action using hole-cross and open field test in mice. The extract displayed dose dependent suppression of motor activity and exploratory behavior in mice in the tested models. The results of the study indicate that the plant possesses strong analgesic and central nervous system depressant activity.