Antinociceptive and anti-inflammatory properties ofRuellia tuberosa

The ethanol extract of Ruellia tuberosa L. (Acanthaceae) was evaluated for its antinociceptive and antiinflammatory properties in experimental mice and/or rat models. In the hot-plate test, the group that received a dose of 300 mg/kg showed maximum time needed for the response against thermal stimuli (5.11 ± 0.12), which was similar to that of diclofenac sodium (5.96 ± 0.18), a well-known painkiller. The maximum possible analgesia (MPH) was 1.93 for the extract dose 300 mg/kg, while that for diclofenac was 2.29 after 60 min of administration in the hot tail-flick method. The extract at 500 and 250 mg/kg doses showed significant reduction in acetic acid-induced writhing in mice with a maximum effect of 63.21% reduction at 500 mg/kg dose, which was similar to positive control diclofenac sodium (66.98%). The extract also demonstrated significant inhibition in serotonin and egg albumin-induced hind paw edema in rats at the doses 100, 200 and 300 mg/kg (serotonin-induced edema 35.85, 46.78 and 55.18%; egg albumin-induced edema 42.96, 48.30, and 55.61% inhibition after 1-4 h). The anti-inflammatory properties exhibited by the extract were comparable to that of indomethacin at a dose of 5 mg/kg (serotonin-induced edema 53.22; egg albumin-induced edema 57.01% inhibition after 4 h).