Effect of alcoholic extract of Tanacetum parthenium on acute pain in rat

  Background: The u se of medicinal plants to reduce pain is important. Tanacetum parthenium has been introduced as an analgesic agent in traditional medicine and is widely used to relieve neuropathic pain and headache.   Objective: The aim of this study was to investigate the analgesic effect of Tanacetum parthenium ethanolic extract on acute pain.   Methods: This study was carried out on 100 male mice weighing 30-35g. Acute pain was investigated using a hot plate test with set point 48 °C and cut off time of 30 seconds. In this experiment 100 mice were divided into 10 groups as follows: 1) control group groups 2-6 received 10, 20, 30, 40 and 80 mg/kg of alcoholic extract, respectively group 7 received 100 mg / kg ibuprofen group 8 received 0.5 mg / kg morphine group 9 received 0.5 mg / kg naloxone and finally group 10 received naloxone and extract. Ethanolic extract of aerial parts was prepared by maceration method and later its analgesic effect was studied at different doses of 10, 20, 30, 40, and 80 mg/kg, i.p. The effect of ethanolic extract and fractions were compared with the analgesic effect of morphine and ibuprofen as standard analgesic drugs. Naloxone was used to study the opioid system.   Data were analyzed by SPSS using Kruskal Wallis test.   Findings: Results obtained from this study showed that the ethanolic extract of Tanacetum parthenium produced an analgesic effect (P<0.05) at two doses of 30 and 40 mg/kg, i.p. The analgesic effect of extract was not lower than that of morphine (10 mg/kg, i.p.), and ibuprofen (100 mg / kg) (P<0.05). Application of naloxone showed no inhibition on analgesic effect of the extract (P<0.05).   Conclusion: The analgesic effect of Tanacetum parthenium was also comparable to that of morphine and ibuprofen, both well known for their analgesic effects. Further investigations to establish a link between the analgesic effect of Tanacetum parthenium and particular phytochemicals, are recommended.