Cocaine has been used for its stimulant properties for centuries. It is derived from the Coca plant and then processed into different forms such as crack (which can be smoked) or powder cocaine. Cocaine is metabolized to three metabolites: norcocaine, ecgonine methyl ester, and benzoylecgonine (BE). Commonly performed immunoassays generally detect BE.
15 Unlike most drug classes that are tested for on immunoassays the cocaine assay is relatively sensitive and specific for cocaine. False negative testing could occur if the urine is collected shortly after use and an insufficient amount of BE has been excreted in the urine. Otherwise, it is a sensitive test to determine recent exposure to cocaine. False positives have not been reported; although it is possible that a positive test could result from drinking Coca tea which is commonly available in South American but is illegal in the United States since does contain small amounts of cocaine.
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