Background/Purpose. To investigate the analgesic and anti-inflammatory effects of a water extract of Hydrocotyle batrachium Hance (HBW) in mice. Methods. The analgesic effects of HBW were investigated by measuring the acetic acid-induced writhing response and the hind paw licking time following formalin injection. λ-Carrageenan (CARR)-induced paw edema was studied to explore the anti-inflammatory effect of HBW. The chromatograms of rutin, quercetin and HBW were obtained by high-performance liquid chromatography (HPLC). Results. Treatment of male ICR mice with HBW (100, 500, 1000 mg/kg) inhibited the writhing response in a dose-dependent manner. The inhibitory effect of HBW at a dose of 1000 mg/kg was similar to that of indomethacin at a dose of 10 mg/kg. HBW significantly inhibited the degree of formalin-induced pain in the late phase. HBW (500, 1000 mg/kg) also inhibited the development of paw edema induced by CARR. The HPLC analysis revealed that rutin was an important bioactive compound in HBW. Conclusion. HBW appears to have analgesic and ant-inflammatory activities.
