A pyrolysis product, anhydroecgonine methyl ester (methylecgonidine), is in the urine of cocaine smokers.

A method using combined gas chromatography/mass spectrometry (GC/MS) for determination of the cocaine pyrolysis product anhydroecgonine methyl ester (AEME) in urine is described. Using this method, we found that human subjects who smoked cocaine under laboratory conditions excreted substantial amounts of AEME in their urine. Little, if any, AEME was excreted in the urine when the same subjects were administered cocaine by intravenous and intranasal routes. AEME may be a useful marker for cocaine (crack) smoking. The pharmacology of AEME is unknown. The possibility that AEME may play a role in the effects associated with cocaine smoking needs to be examined.