EVALUATION OF THE ANALGESIC ACTIVITY OF THE LEAF METHANOLIC EXTRACT OF ZANTHOXYLUM OVALIFOLIUM WIGHT

Abstract

Background: Zanthoxylum ovalifolium is a medicinal shrub used by some communities of Karnataka, India, in treating fever, headache and other 
ailments. Objectives: The present study is to evaluate the analgesic activity of the Z. ovalifolium methanolic leaf extract. Method: Standard in-vivo 
methods such as acetic acid-induced abdominal writhing, tail immersion and hot plate analgesic methods using albino Wistar mice. Dose levels such 
as, 100, 200 and 400 mg/kg body weight of the extract were given orally by gastric gavage and the obtained results was compared with a standard 
acetylsalicylic acid (aspirin) (400 mg/kg) and negative control. Statistical analysis was done using Prism using one-way ANOVA. Result: In the acetic 
acid-induced writhing model, the Z. ovalifolium methanolic extract (400 mg/kg) and the reference drug significantly (P<0.0001) decreased the number 
of abdominal constrictions in the tested mice. The percentage inhibition of the abdominal constriction was improved from 0% (100 mg/kg) to 40% at 
the highest dose of the extract (400 mg/kg). In the tail immersion method, the Z. ovalifolium methanolic extract (400 mg/kg) appreciably (P<0.0001) 
increased the pain reaction time. In hot plate method the extract and Aspirin drug showed significant antinociceptive effect in the tested animals (P< 
0.0001) which increases the mean pain reaction time at the doses of 200 and 400 mg/kg. From One-way ANOVA followed by Dunnett’s multiple 
comparison test showed significant results in all tested analgesic experiments with P value is less than 0.0001 against control.  Conclusion: Z. ovalifolium 
methanolic extract demonstrated significant analgesic activity which influencing both central and peripheral pain suppression pathway.