RESUMO
Pain has been defined by International Association for the Study of Pain as an obnoxious sensory and emotional incident allied with actual or potential tissue damage. Artemisia annua (Asteraceae) is native to China . Its ancient Chinese name, Qing Hao, literally means “green herb A. annua L. is a source of both essential oil (1.4 – 4.0 %) depending on chemotype, and other substances such as sesquiterpene lactones, flavonoids, polyalkynes and coumarins. The essential oil composition has been studied thoroughly and about 60 components have been identified; camphor, artemisia ketone, germacrene D and 1,8-cineole, are usually the main components.The professed medical uses of artemisia annua include treatment for malaria, infections, fever, inflammation, bleeding, headaches and cancer, particularly some lung and thyroid cancers. The ethanolic extract of aerial parts of Artemisia annua (200mg/kg) was found to be effective against chemical as well as thermal stimuli. So the results are in agreement with the traditional use of plant as analgesic agent.