Study of the Analgesic Effect of Hydro-alcoholic Extract of Red Lentil in Rat by Formalin Test

Due to the increased role of medicinal plants in therapy, the aim of this research was to study the analgesic effect of hydroalcoholic extract of the red lentil and to compare it with morphine and aspirin as common analgesics. In this experimental study, Wistar male rats were divided into six groups of 6 rats, randomly. Negative control group (normal saline 5ml/kg); two positive control groups morphine (2.5 mg/kg) and aspirin(300mg/kg) and three treated groups (100, 200 and 400 mg/kg) received a single dose of hydroalcoholic extract of red lentil via intrapritoneal respectivals. In this study, the analgesic effect was investigated by using formalin test. The results revealed that the red lentil extract has dosedepended analgesic effect was 200 mg/kg. There was not any significant difference between 200mg/kg and 400mg/kg of extract in all of time of study. Our results showed that the analgesic effect of best effective dose (200mg/kg) on acute pain had not significant difference with morphine and aspirin in other hand the effect of extract (200mg/kg) on chronic pain was less than morphine and more than aspirin. The results indicate that the analgesic effect of hydroalcoholic extract of red lentil can probably be due to the influence of the antioxidants of this extract.