Cocaine (COC)

CPT Code: 80101
Specimen: Urine
 

Volume:

30 mL
Container:

Use plastic urine drug bottle and evidence tape or tamper-evident container for forensic specimen. Collection kits are available by request from the laboratory.

Collection:

Urine specimens may be collected in plastic (i.e., polypropylene, polycarbonate, polyethylene) or glass containers.  Some plastics can absorb certain drugs.

Fresh urine specimens do not require any special pretreatment.  No additives or preservatives are required.  Boric acid should not be used as a preservative.

Specimens may be encountered that display turbidity.  It is recommended that such specimens be centrifuged before analysis.

Specimens should be within the pH range of 5-8.  Specimens with a pH outside this range should be adjusted to this range by the addition of 1N HCl or 1N NaOH before analysis.

Specimens should be at a temperature of 20-25 ⁰C before analysis.

Frozen specimens must be thawed and mixed thoroughly prior to analysis.

Stability: If not analyzed immediately, specimens should be stored refrigerated for less than 24 hours.  Specimens should be frozen if storage longer than 24 hours is required.
 Cutoff: 150 ng/mL
 Note: This method provides only a preliminary analytical test result.  A more specific alternate chemical method must be used in order to obtain a confirmed analytical result.  Gas chromatography/mass spectrometry (GC/MS) is the preferred confirmatory method.  Other chemical confirmation methods are available.  Clinical consideration and professional judgment should be applied to any drug of abuse test result, particularly when preliminary positive results are used.
 Use: Measurements obtained with COC method are used in the diagnosis and treatment of cocaine use or overdose.
Information: Cocaine is a central nervous system stimulant that is extracted from the coca plant.  As a drug of abuse, it is self administered in a variety of ways, including inhalation and intravenous injection.  Cocaine base can be smoked in a form that is commonly known as “crack”.  Cocaine is rapidly absorbed, especially when smoked.  While all forms are potentially addicting, “crack” is especially likely to lead to dependence because of its more rapid and heightened effect on the abuser.
Excretion rate patterns vary with the mode of administration and from individual to individual.  Cocaine is almost completely metabolized, primarily in the liver, with only abount one percent excreted in the urine unchanged.  Most cocaine is eliminated as benzolecgonine, the major metabolite of cocaine.  Cocaine is also excreted in relatively lesser amounts as ecgonine methyl ester and ecgonine.  Cocaine metabolites may be detected in urine for up to a couple of days after cocaine is used.  Benzolecgonine can be detected in urine within four hours after cocaine inhalation and remain undetectable in concentrations greater than 1000 ng/mL as long as 48 hours.
Methodology:

EMIT®