Alcohol-specific cocaine metabolites in serum and urine of hospitalized patients.

The serum and urine from 44 consecutive patients that tested positive for the cocaine metabolite benzoylecgonine (BE) were examined for free cocaine, ecgonine methyl ester (EME), and other metabolites by gas chromatography/ion trap mass spectrometry (GC/MS). In 13 of these patients, unique ethanol-related cocaine metabolites, cocaethylene and ecognine ethyl ester (EEE), were detected in urine and serum. One was from a newborn baby whose mother's blood was positive for cocaine and negative for cocaethylene. In two other patients, isopropanol was also consumed with cocaine and ethanol. In one of these two, cocaisopropylene and ecognine isopropyl ester (EPE) were identified in urine. The urine ethanol concentration in 7 of the 13 cocaethylene-positive patients ranged from 19 to 322 mg/dL. In the other six, ethanol was not detected in the urine. However, each of these latter patients had either prior serum results that were positive for ethanol or admitted to recent alcohol abuse. In the remaining 31 of 44 cocaine-positive patients, ethanol and the alcohol-specific cocaine metabolites were absent. The detection of alcohol-related cocaine metabolites is fairly common in a cocaine-positive patient population.