Cocaine Confirmation, Urine
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Cocaine is a drug of current health concern because of its proliferation among recreational drug abusers.
Freebase and crack increase the potential for major cocaine toxicity. Cocaine use is declining across the nation according to the National Institute of Drug Abuse.
Increasingly, laboratory results are disputed or there are medical/legal overtones. Therefore, physicians are finding an increased need to confirm positive results before informing or confronting the patients.
Detecting and confirming drug abuse involving cocaine
The presence of cocaine, or its major metabolite, benzoylecgonine, indicates use within the past 4 days.
Cocaine has a 6-hour half-life, so it will be present in urine for 1 day after last use.
Benzoylecgonine has a half-life of 12 hours, so it will be detected in urine up to 4 days after last use.
There is no correlation between concentration and pharmacologic or toxic effects.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Not intended for use in employment-related testing.
For situations where chain-of-custody is required, a Chain-of-Custody Kit (Supply T282) is available. See COCH/9426 Chain-of-Custody-Processing.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Positives are reported with a quantitative GC-MS result.
COCAINE BY GC-MS
BENZOYLECGONINE BY GC-MS
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Baselt RC, Cravey RH: Disposition of Toxic Drugs and Chemicals in Man. Third edition. Chicago, Year Book Medical Publishers, 1989
2. Langman LJ, Bechtel L, Holstege CP: Chapter 35. Tietz Textbook of Clinical Chemistry and Molecular Diagnostics. Edited by CA Burtis, ER Ashwood, DE Bruns. WB Saunders Company, 2011, pp 1109-1188