Benzoylecgonine is the compound tested for in most substantive cocaine urinalyses. It is the corresponding carboxylic acid resulting of the hydrolysis of the methyl ester of cocaine. It is formed in the liver by the metabolism of cocaine, catalysed by carboxylesterases, and subsequently excreted in the urine. It can be found in the urine for considerably longer than the cocaine itself which is generally cleared out within 5 days. Small amounts may be traced back to certain OTC (over the counter) medications, after having been metabolized in the liver.
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