Dual effect of Toxicodendron pubescens on Carrageenan induced paw edema in rats

BackgroundToxicodendron pubescens is the current botanical name of homeopathic Rhus toxicodendron (Rhus tox). Rhus tox drug is widely used in homeopathically diluted form in the treatment of inflammatory and edematous conditions. We studied the effect of crude form of this plant, after single and multiple doses in Carrageenan induced paw inflammation in rats.MethodWe evaluated effects of single dose and multiple doses of orally administered Rhus tox on Carrageenan induced paw inflammation in rats. We tested 10 mg/kg, 20 mg/kg and 40 mg/kg doses of Rhus tox.In the single dose study, Rhus tox was administered 1 h prior to the subplantar injection of Carrageenan. In the multiple dose study, Rhus tox was administered twice daily for three days and Carrageenan was injected 1 h after the last dose.Paw volume was measured using a digital plethysmometer.ResultsAdministration of a single dose of Rhus tox 1 h prior to injection of Carrageenan significantly reduced the paw inflammation in a dose dependent manner. Administration of multiple doses of Rhus tox increased the intensity of inflammation induced by Carrageenan, but this was not statistically significant.ConclusionRhus tox, in crude form, exerts anti-inflammatory effects after a single dose and proinflammatory effect after multiple doses in Carrageenan induced paw inflammation in rats. Further study is needed to explain this dual effect.