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Question: Utox

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As part of the work-up for abnormal behavior in a 3 year old, the qualitative urine drug screen comes back positive for a substance. 

Which of the following is LEAST likely to be a false positive utox from a therapeutic medication?
12 votes

pemsou5_wp • May 18, 2021

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  1. Kelly May 18, 2021 - 9:31 pm Reply

    E) Cocaine
    Qualitative urine drug screens typically are immunoassays using antibodies to detect the presence of drug metabolites. For some drugs, other substances (medications, foods, household products) can potentially cross-react with the antibodies and result in a false positive. False positives occur most commonly for amphetamines, from substances such as pseudoephedrine, bupropion, labetalol, ranitidine, and metformin. Poppy seeds, quinolones, and rifampin can cause a false positive for opiates. NSAIDs, PPIs, and baby wash products have been associated with false positives for cannabis. Several medications can cause a false positive for PCP. Coca leaves can cause a false positive for cocaine; however, no therapeutic medications commonly cause a false positive cocaine result.

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