A previously published simple and sensitive high-performance liquid chromatographic method for determination and identification of rutaecarpine in rat plasma was used for evodiamine determination. However, the ultraviolet detection was not 344 nm, but 227 nm. The method was applied to a pharmacokinetic study of evodiamine in rats after 2 mg/kg intravenous administration. A biphasic phenomenon with a rapid distribution followed by a slower elimination phase was observed from the plasma concentration-time curve. Compartmental analysis yielded a two-compartment model.