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    false positive for marijuana use in pt. using oxybutynin cl
    An_248025 posted:
    I have been on Oxybutynin Cl for approxomatealy two years to control a spastic bladder..i inadvertantly ate a "krispies treat" that had been loaded with marijuana approximately August 4th, 2012. I had a yearly physical with my physician on August 21,2012. At that time i provided a uriine sample for testing. I am on prescribed Fentynal patches 25 and 50 mcl/three days and oxycondone 30 mg. 6 per day for the past 2+ years, along with clonazepam 0.5mg bid as needed...I have tested positive three times on a drug screen for marijuana. the first one being on august 21, 2012, the second august 2012 and the last on september 19th, 2012. how is it possible that there is still marijuana in my urine for over 6+ weeks? Is it possible that because i take the Oxybutynin CL that a drug screen for marijuana shows up as false positive...I am truly grateful for any feedback i receive on this question..
    Anon_3114 responded:
    If you're overweight, marijuana can show up on drug tests up to a month after use. The metabolites in THC adhere to your fat cells, and slowly release.
    Betty Ford Center
    James Golden, MD responded:
    There are actually many drugs that may show up as a positive screen for cannabis on a dipstick urine test. However, a confirmatory test should be negative in that case, so you wouldn't have to identify Oxybutynin as the reason for the positive test.

    It's hard to incriminate that single "treat" as responsible for a positive test six weeks later, but when it comes to cannabis and urine drug testing, anything is possible.

    I'm interested about the frequent drug testing. Was this is a one-time thing?

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