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Q: Urinalysis THC false positive ( Answered 5 out of 5 stars,   0 Comments )
Subject: Urinalysis THC false positive
Category: Health > Medicine
Asked by: pjar67-ga
List Price: $20.00
Posted: 15 Dec 2005 21:44 PST
Expires: 14 Jan 2006 21:44 PST
Question ID: 606409
I have tested "positive" for THC twice,30 days apart,for a county
probation dept. They use a 50 ng/ml litmus strip for testing. I have
not smoked marijuana for three years and do not do any other drug. My
roommate did smoke in front of me,but only until 3 weeks before my 2nd
positive. I take: "Omeprazole 20mg SA" time release capsules,a Proton
Pump Inhibitor(PPI),for acid reflux. "Gemfribrozil 600mg" tablets for
above normal cholesterol/triglycerides due to poor excercise and less
than adequate diet,but am not in poor health. I drink wine and smoke
ultra-light cigarettes on an almost daily basis. I can't think of any
other consistent influences which might cause what I know is a false
positive. Anything you can tell me will help my research. Thank You
Subject: Re: Urinalysis THC false positive
Answered By: sublime1-ga on 15 Dec 2005 23:29 PST
Rated:5 out of 5 stars

I worked in the field of mental health for 25+ years, and
drug testing was a common reality. One of the facts which
should be well-known to anyone in the field is that THC 
gets stored in the fat cells, so if one is at all overweight
it's likely that they have THC stored. If the person then
exercises during the week of testing, it can result in the
release of sufficient THC metabolites into the bloodstream
to yield a positive test, since the test looks for metabolites,
and not THC itself. So you won't get stoned when the metabolites
are released into your bloodstream when you exercise, but the
test will still detect them. It can take several years for these
metabolites to be released and excreted from the body, so false
positives in former cannabis users are not uncommon, and this 
should be taken into consideration by test reporting agencies.

Even normal activities of daily life and the concurrent level
of metabolism can and will release THC metabolites into the
bloodstream, and can produce a false positive.

From the  Walter J. Freeman Neurophysiology Lab website at
the University of California at Berkeley, a term paper on
Marijuana confirms this:

"THC is fat-soluble and gets stored in the fat cells. Since
 fat cells secrete THC metabolites over an extended period
 of time, cleaning out the body from this substance is 

Much more on the page:

This page on 'How To Pass a Drug Test' from
expands on this topic:

"Athletes have a big advantage over normal civilians. When
 fat is burned, THC byproducts are released into the blood.
 This is the only way to get THC metabolites out of lipid
 tissue. 'Normal living will burn them slowly, as your fat
 reserves get turned over' (Dr. Grow). Due to an athletes
 high metabolic rate, THC moves through an athletes system
 significantly faster. Exercising between drug tests will
 clean THC metabolites from the system at a faster rate,
 thus lowering the detection period. It is important to
 stop burning fat cells near test time. On test day, it
 doesn't matter what's in your lipid tissue. What's in
 your blood and urine does matter.

 Exercise increases the amount of THC metabolites in the
 urine; so quit exercising a week before the test. Be
 lazy, and eat big. This will put the body in an anabolic
 fat-storing stage. At this point, the 'buried' THC
 metabolites won't escape and go the the urine."
See section 6.8:

Please do not rate this answer until you are satisfied that  
the answer cannot be improved upon by way of a dialog  
established through the "Request for Clarification" process. 
A user's guide on this topic is on skermit-ga's site, here: 

Additional information may be found from an exploration of
the links resulting from the Google searches outlined below.

Searches done, via Google:

THC  "fat cells"

Request for Answer Clarification by pjar67-ga on 19 Dec 2005 20:30 PST
Your response seems to fit me to a T. Thank you. 
However,what about a "no" or "not likely" to my inquiries about my
medications and wine-drinking? Just want to clarify.
How do I find a lab which will show (what I know) the court? 
I will gladly increase my $ offer.

Clarification of Answer by sublime1-ga on 19 Dec 2005 21:38 PST

In my experience in the field, I never heard of wine
or smoking having any impact on the release of THC

As for the meds, I would say, "not likely", but I'm
not an expert on medicinal interactions, so I suppose
it's possible that, e.g., Gemfribrozil for above normal
cholesterol/triglycerides, having some impact of fats
in the blood, might have some effect on fats stored in
the muscle tissues, but realistically, the relationship
of a drug to the metabolism of THC is not the sort of 
thing which is studied and released with regard to the
effects or side effects of a medication, and the data
has to exist before I can find it via research.

As for other labs, I would expect they would have
similar findings. It's not the findings that are in
error, it's the failure to take into account that the
presence of THC can be a normal result for many months
after the last use, especially if a person has a high
percentage of body fat. I would approach the court with
documentation, or solicit someone who has worked in the
field of chemical dependency (CD) to back you up on this.

In your situation, correct interpretation of the test
results is much more important than the results themselves.
The labs themselves are not necessarily experts on the
significants of the results, and CD counselors and therapists,
are much more likely to be familiar with what I'm suggesting
in the way of interpretation of the results.

Let me know if that clears things up, or what else I can
reasonably do to assist you.

pjar67-ga rated this answer:5 out of 5 stars
Thank you sublime. You have definitely helped.
Thank you to Google for offering such an open forum.
You are both to be commended.

There are no comments at this time.

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