|SOFT - TIAFT 1998||Scientific Session 3||Thursday October 8, 1998|
|COCAINE HALF LIVES IN DRUG ABUSING PATIENTS PRESENTING TO THE EMERGENCY DEPARTMENT|
|Kari E. Blaho, Stephen L. Winbery, Barry K. Logan1, Lynda J. Park, Steven A. Karch2|
Department of Emergency Medicine, UT Medical Group, Memphis, TN, USA
|Cocaine half life has been previously reported to be 30-90 minutes in human volunteers and has been postulated to be accelerated by the presence of elevated temperatures. We report the half life of cocaine in patients presenting to an inner city emergency department (ED) for treatment of acute cocaine intoxication.
Blood for cocaine and metabolite concentrations was drawn as soon as feasible after arrival and at intervals thereafter and frozen immediately. Concentrations were determined by an extractive alkylation/GCMS procedure. The mean age of the patients was 24.4 ± 7.3 years; 2 were female, 8 were male. Two patients ingested crack, 2 were IV users, 1 insuflated, 2 smoked crack cocaine, one both smoked and ingested crack. Two patients were admitted to the ICU, two were admitted to floor beds and 6 patients were discharged from the ED. One patient died.
Pharmacokinetic modeling revealed that the half life for cocaine ranged between 64 and 93 minutes for all patients and the mean initial cocaine concentration was 0.606 ± 0.478 mg/L. Metabolite concentrations (mg/L) were as follows: Ecgonine methylester 0.471 ± 0.382, ecgonine 0.454 ± 0.387, and bezoylecgonine 2.047 ± 2.986. Cocaethylene was not detected in any patient and norcocaine was detected in 3 patients with a mean concentration of 0.261 ± 0.436. Route of administration, body temperature, initial concentration, degree of hydration and presence of other drugs did not have a clinically significant effect on cocaine clearance. In addition, cocaine concentrations varied widely and were not predictive of the severity of clinical findings or outcome.