Comprehensive review of cocaethylene and cocaine concentrations in patients.

Cocaethylene (CE) and cocaine (COC) concentrations were reviewed for 41 patients studied by this laboratory and found to have measurable CE in plasma. In 17 instances, urine concentrations of CE and COC were also measured. In 15 cases other drugs in addition to COC and ethanol (ETOH) were detected. Thirty-three cases involved trauma. For the entire series, ages ranged from 19 to 48 years (mean 31 years) with men accounting for 36 cases. Mean concentrations were as follows: plasma CE, 353 nmol/L (range 16.1-1,959); plasma COC, 386 nmol/L (range no measurable amount-1,455); and whole-blood ETOH, 36.5 mmol/L (range no measurable amount-110.9). The ratio CE:COC in plasma ranged 0.1 to 4.7 (mean 1.3). Concentrations of ETOH in whole blood showed significant negative correlation with plasma COC (r = -0.425, P < .01). In addition, plasma CE concentrations showed significant correlation with plasma COC (r = 0.422, P < .01). When available, urine concentrations of CE and COC showed significant correlation with their concentrations in plasma (r = 0.821, P < .01; and r = 0.569, P < .05, respectively). As in plasma, urine concentrations of CE showed significant correlation with urine COC (r = 0.831, P < .01).