Antiinflammatory effects of a combined herbal preparation (RAH13) of Phellodendron amurense and Coptis chinensis in animal models of inflammation

In an attempt to develop an antiinflammatory herbal remedy that is as potent as current synthetic medicines, the cortex of Phellodendron amurense Rupr (Rutaceae) and the rhizomes of Coptis chinensis Franch (Ranunculaceae) were combined in a 2:1 ratio. This ratio was chosen based on in vitro experiments and traditional Asian medicine prescriptions. The combined ethanol extract, named RAH13, was evaluated for antiinflammatory properties using animal models of acute inflammation such as the croton oil‐induced ear edema test and an acetic acid‐induced capillary permeability test. Models of chronic inflammation were also tested using the cotton pellet test and a delayed‐type hypersensitivity (DTH) test. Oral administration of RAH13 at a dose of 200 mg/kg showed in vivo antiinflammatory activity as potent as the effects associated with 100 mg/mL of celecoxib or 1 mg/kg of dexamethasone. These effects were seen in both acute and chronic inflammation models, suggesting that RAH13 may be effective in controlling some inflammation‐related diseases. Copyright © 2007 John Wiley & Sons, Ltd.