Evaluation of the analgesic and anti-inflammatory effects of Harpagophytum procumbens in albino rats: a comparative study with indomethacin and rofecoxib

ABSTRACT

Harpagophytum procumbens [Harpago.] is a herpaceous plant. It has been used in traditional medicine for treatment of many diseases including headache, rheumatic diseases and inflammations. The aim of the present study is to evaluate the analgesic and anti-inflammatory effects of the herpal plant on the experimentally-induced acute inflammation [carrageenan-induced edema test] and chronic inflammation [Freund's adjuvant-induced arthritis] in adult male albino rats. In addition, these actions were compared with that of indomethacin and rofecoxib. The results of the present work revealed that Harpago. aqueous extract and indomethacin, completely, prevented the carrageenan-induced paw edema. Also, they significantly increased the paw withdrawal latency [reaction time] that reflects the analgesic effect of the drugs. The intensity of the latter effects reached maximum level when measured after 1-2 hours for both drugs. Meanwhile, rofecoxib produced significant reduction in the paw edema that induced by carrageenan and elicited an analgesic effect that reached maximum level after 3-4 hours from carragednan injection. Concerning the chronic anti-inflammatory effects, Harpago-protected the knee joint from the Freund's adjuvant-induced degenerative changes, however, this protection is much less than that produced by each of indomethacin or rofecoxib. Thus, it could be concluded that Harpagophytum procumbens has analgesic and anti-inflammatory effect in the acute and chronic inflammatory conditions which is more prominent in the acute and subacute inflammations; and its duration of action is similar to indomethacin, but shorter than that of rofecoxib