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    Naproxen 500 mg
    hunter0177 posted:
    My son was recently prescribed Naproxen 500 mg for a back injury. During a weekly drug test, after taking this medicine, he tested positive for THC. I have spent hours researching this and every thing i find says that it will in fact cause a false positive.(including this web site)

    I took my son to his regular physician to get yet another drug test today to further prove that my child was not positive for THC. When I approached the drug court with my findings I was basically called a liar and told that I could find anything on the internet. This false positive, if pushed without evidence could cause my child to be kicked out of school. Are there any studies by the fda or any drug manufacturers to back up my claim?
    Betty Ford Center
    A Thomas McLellan, PhD responded:
    The possibility of a false positive result does exist, although it is highly unlikely, with an occurrence of approximately 1 - 2%. Put differently, urine drug screens are at least 98% accurate regardless of what other substances may have been taken.

    However, all initially positive screenings should be followed with a second, more selective, confirmatory test to rule out any false positives. Using two different tests on the same sample makes the likelihood of a false essentially 0.

    The current standard confirmatory test is gas chromatography/mass spectrometry (GC/MS). If that confirmation is positive, then it is certainly a truly positive test.

    I am skeptical that the initial reading was wrong, but regardless, it is certainly within your rights to ask for the confirmatory test, on the same sample.

    The following resources have additional information about drug testing:
    Drug Testing (US Dept. of Labor)
    Drug Testing & Workplace Issues (NIDA)
    mary1995 responded:
    this happened to me with tested positive for cocaine. i made copies of my proof off the internet and the judge excused me
    2win1 responded:
    Doctors are money grubbing parasites, that reap remuneration from human suffering. This attitude is very prevalent among the seasoned physicians. The FDA is full of dam asses whose principal intent is to sell out to the premier directives. I suggest you contact the Department of Human Services or the National Institute of Health. God Bless you and your son. 2win1

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