Abstract

The crude methanol leaf extract of Olax subscorpioidea has been reported to possess analgesic and antiinflammatory activity. The present study therefore aims to investigate the analgesic and anti-inflammatory activities of the liquid-liquid partitioned leaf fractions. The oral median lethal dose of the fractions was determined using method of Lorke. The analgesic activity was evaluated using acetic acid-induced writhing, formalin induced pain and hot plate tests in mice, while the anti-inflammatory activity was evaluated using carrageenan-induced hind paw oedema model in rats. Preliminary phytochemical screening of the entire fractions was also conducted using standard method. The oral median lethal dose values  of the aqueous and butanol fractions was found to be greater than 5,000 mg/kg in mice and rats while that of the hexane fraction was estimated to be 2,154mg/kg in mice and 3,808mg/kg in rats respectively. The acetic acid induced writhes and the formalin induced pain leaking effect were significantly (p<0.01, p<0.001) reduced by the fractions. The hot plate latency was significantly (p<0.01, p<0.001) increased in the fractions (except hexane fraction). The paw oedema was also significantly (p<0.05, p<0.01, p<0.001) reduced by the fractions as compared to that of the control. Preliminary phytochemical screening revealed the presence of saponins, tannins, steroids, cardiac glycosides, flavonoids, alkaloids and carbohydrates in all the fractions except for the ethyl-acetate fraction which is devoid of saponins. The results suggest that O. subscorpioidea leaf fractions possess effective analgesic and anti-inflammatory activities mediated via peripheral and central mechanisms.