The Analgesic Effect of Ethanolic Extract of Tanacetum Parthenium in Acetic Acid Model

Background: Different Tanacetum species have been widely used in traditional medicine
as a remedy for the pain and inflammation since ancient times. Because of the few studies
conducted on the mechanism of Tanacetum parthenium (TP), this study has been
conducted to determine the effects of TP on pain relief and its action mechanism.
Materials and Methods: In this experimental study, 100 male mice (25-35 g) were
randomly grouped into receivers of distilled water, morphine (0.5 mg/kg), ibuprofen (100
mg/kg), different doses of the extract including 10, 20, 30 and 40 mg/kg of the extract. In
order to study the pain relief effect of this herb, two groups were also received naloxon
(0.5 mg/kg) and naloxon together with the 40 mg/kg of the extract. Animals were injected
with 0.9% acetic acid for visceral pain induction. 15 minutes after each injection
antinociceptive effects were recorded by counting the number of writhes for 30 minutes.
Achieved data were analyzed by SPSS statistical software, Kruskal-Wallis and Dunn post
hoc test.
Results: 40 mg/kg of the extract of TP caused a significant reduction in the pain response.
Group receiving a dose of 40 mg/kg extract had higher antinociceptive effects than the
group receiving ibuprofen (p<0.001) but it didn't have any significant difference with the
group receiving morphine. Group receiving naloxone had a statistical significant
difference with the group receiving 40 mg/kg extract with naloxone and the group
receiving 40 mg/kg extract (p<0.001).
Conclusion: Antinociceptive activity of TP extract is due to the activation of opioid
system, however further studies are needed to be conducted for finding out the suitable
position or the role of the antispasmodic effect of TP.