Analgesic and anti-inflammatory activity of Crinum glaucum aqueous extract

The anti-inflammatory and analgesic effects of the aqueous extract of Crinum glaucum were evaluated in mice and rats using the carrageenan- and dextran-induced paw oedema, acetic acid-induced writhing, cold water tail flick and formalin pain tests. The extract (100-400 mg/kg) and acetylsalicylic acid (100 mg/kg) produced a significant (P<0.05) inhibition of the second phase response in the formalin pain model, while only the high dose (400 mg/kg) of the extract showed an antinociceptive effect in the first phase. The extract also showed a dose-dependent inhibition of acetic acid-induced abdominal writhes. The tail flick latency was dose dependently enhanced by the extract but this was significantly (P<0.05) lower than that produced by morphine (2 mg/kg). The extract (125-500 mg/kg) administered 1 h before or after carrageenan-induced paw swelling produced a dose dependent inhibition of the oedema. No effect was observed with the dextran-induced oedema model. The data obtained suggest that the anti-inflammatory and analgesic effects of the extract may be mediated via both peripheral and central mechanisms.