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    False Negative
    Tommysdad posted:
    I have been prescribed valium and norcos for cronic pain.I have degeneration of the disc in my low back and neck.I take my meds the way they are prescribed.I went to my doctor about a week ago,thinking there was know problem,when my doctor tested me for my meds.I was NOT worried at all.She comes back saying there was NOTHING in my urine.I was mortified.I asked her to test me again,she wouldnt.I drink SOY MILK.some people says that that may be blocking it.I had taken my meds the way they were prescribed.Does anyone have any suggestions?She told me this was my last month but,she would still continue seeing me though for other health problem.
    annette030 responded:
    What kind of drug test did you have? Did they test for Valium and hydrocodone? I would ask the doctor to call the lab involved and discuss this all with them. They may have had others report the same thing.

    I have personally never heard of soy milk causing a problem with drug tests.

    Take care, Annette
    David Maine, MD responded:
    Norco contains Hydrocodone and Tylenol. Hydrocodone undergoes metabolism via a an enzyme called CYP2D6. One of the metabolites of Hydrocodone is Hydromorphone which then undergoes a second phase of metabolism called glucoronidation. False negatives are rare unless use is sporadic. If so, then a false negative could potentially me caused by being a rapid metabolizer with subsequent clearance. Other considerations for a false negative include running the test incorrectly, incorrect sample, and/or assay problems. I would discuss this with your doctor and perhaps ask your doctor if he could discuss with the lab toxicologist. Have you had problems with toxicology screens before or was this your first one. I hope this helps. Good luck.
    Tommysdad replied to annette030's response:
    The type of test used was non-controlled test.I also had the TFSI injections,ECX/S injections,twice with this one. Thank you for your responce.
    Tommysdad replied to David Maine, MD's response:
    Thank you for responding.The type of test used was a non-controlled test.Plus,I failed to mention that I have had the TFSI injection once.Then,I have had the ECX/S injections,twice.Maybe that has blocked something.Thank you again.

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