Ecgonine Methyl Ester, a Major Metabolite of Cocaine

Most assays for the identification of cocaine use are aimed at detection of benzoylecgonine, a major urinary metabolite. Gas chromatography assays require derivatization of benzoylecgonine. Recently, ecgonine methyl ester (methylecgonine) has been shown to be major urinary metabolite of cocaine in man after oral administration. These results indicate that ecgonine methyl ester is a prominent urinary metabolite after street use of cocaine, which primarily involves intranasal application and intravenous injection rather than ingestion. Advantages of GC/MS analysis for ecgonine methyl ester in identifying cocaine use include the ability to chromatograph it on common stationary phases without derivatization and its early elution.