ABSTRACT
Background: Operculina turpethum Linn. (Convolvulaceae) is commonly called “Trivrit” or “India jalap” in English. It is a perennial herbaceous plant with purplish stem and milky-white exudates. This study was aimed at evaluation of the analgesic and antioxidant effects of the methanolic extract of O. turpethum leaves in mice. Methods: The acute oral toxicity of the extract was evaluated using up and down method. The analgesic effects were assessed using acetic acid-induced abdominal writhing reflex and tail flick methods, while the antioxidant activity (AA) was assayed using photometric 2, 2-diphenyl-1-picrylhydrazyl free radical scavenging assay method. Results: The extract produced a concentration-dependent increase in the AA with inhibitory concentration 50% >400 μg/ml. The extract (100, 200 and 400 mg/kg) and aspirin (100 mg/kg) produced a significant (p<0.05) dose-dependent reduction in the number of abdominal constriction induced by intraperitoneal injection of acetic acid in treated mice when compared to the distilled water treated mice. The extract (100, 200, and 400 mg/kg) and pentazocine (3 mg/kg) caused a significant (p<0.05) dose-dependent increase in the pain reaction time in the treated mice groups, when compared to the distilled water treated groups. Conclusion: The study showed that O. turpethum possesses analgesic and antioxidant properties and confirmed the folkloric use of O. turpethum leaves in the traditional pain management.