The Role of Ethanol in Cocaine Concentration in Human Post-mortem Whole Blood

Regardless of its form, the coingestion of cocaine (COC) and ethanol is still a very important problem in drug abuse. The formation of the transesterification byproduct, cocaethylene (CE), which has lower LD50 has led to the idea that the combination of the two drugs is more toxic (lethal) than just cocaine individual response and that smaller concentrations of the drug concentration should be present in those related cocaine deaths.The aim of this study was to evaluate the role of ethanol as an agent of interaction in lethal intoxication and to establish the influence of CE in post-mortem whole blood cocaine concentration. Thirty six post-mortem cases, in which cocaine was the only cause of death, were compared to eighteen cases of cocaine/ethanol interaction in terms of COC, benzoylecgonine (BE) and ecgonine methylester (EME) concentrations. Cocaine and cocaethylene, BE, EME concentrations correlated positively, but CE concentrations did not correlate with blood ethanol. When the correlation of each metabolite and the precursor were analyzed statistically by Manova, no differences between the two groups were found. The ratio of BE and COC concentrations (BE/COC) for cocaine as the only drug was statistically greater than BE/COC when ethanol was present. On the other hand, statistics with Manova (Wilks l test, a = 0.05) showed that there is a significant difference between the two groups when COC and its main products of biotransformation, BE and EME were focused on variables.