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Family Physician
Family Physician, Board Certified MRO
Category: Drug Testing
Satisfied Customers: 12816
Experience:  Medical Review Officer - Physician Trained and certified in drug test interpretation
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I have tested positive for benzodiazepine in a police

Resolved Question:

I have tested positive for benzodiazepine in a police urinalysis but I am not taking a benzodiazepine drug - how can this be?
(I am currently taking Prozac & Oxycontin & Oxynorm for chronic back pain.)
I would really appreciate your opinion.
Submitted: 6 years ago.
Category: Drug Testing
Expert:  MugsyMD replied 6 years ago.
You should not be testing positive for a Benzo if all you are taking are prozaxc, oxycontin, and oxynorm. That would be impossible. Did they test you positive for your other drugs, because if they did not test you for the oxy, and you were negative for this, then they had the wrong urine.
Expert:  Dr. Lori replied 6 years ago.

HI there-

I have a different answer-

If this test you did was a simple cup test for a set of drugs, and it tells only positive for the drug class, there is a possibility you could have a false positive, and when they send the urine for confirmatory testing, it will not show a + Benzo test.

When the GC-MS confirmation test is done, it measure the exact drugs in your system down to the nanogram.

We know, that on some UDS (urine drug screen) we see a BENZO + for Sertraline, which is an antidepressant in the Prozac family (SSRI), Sertraline is Zoloft. Despite this association, these are chemically different structures. I don't think this is the cause.

Also- Rohypnol has given many a false + on a urine drug screen. This is what otherwise is caled "Roofies" or the "date rape drug",. if you ever felt like you were falling asleep, or passing out for no known reason at a it possible your drink etc was laced or tampered with this, you might not even remember it. So any recent lapse in your memory? This could be explained by a Roofies and cause the result you have..

We know the anti-inflammatory drug Oxaprosin also gives us a false +. for Benzos. And the prescribing info for this drug now talks about causing a false + for Benzos.

So- basically the problem is Manufacturer specific- each drug screen tests will have drugs that cause a false positive.

The tests can detect some of these drugs up to 30days. So-- any test/procedure/exam you may have had could have called for an injection of a benzo that you are test + for...But if you had no ERvisits, no tests at the hospital, no minor surgeries... No reason for you to have a true +.

So-- the conclusion-

Your urine needed to be and needs to be sent to lab for verification. When the lab does the GC-MS, ALL the drugs that caused a + on the screen will not show up,

and therefore confirm that YOU DID NOT test + for Benzo at all. And then-- you can feel confident that you have a UDS that only shows false positives, not true positives, and a GC-MS confirmation they are not in your system!

That is what You need it sent out for-- you need the GC-MS.

And, make sure what you DO take is in there as a real +.

So- you should test + only for OXY!

I hope that helps--

Here is some info:

ZOLOFT test +:

The Rest:

I hope this helps you--

But you want to see your GC-MS--

And any decision made by the UDS is an incorrect one.

Let me know if you have any questions, glad to clarify.

If this answered your question well, please click ACCEPTso I may receive creedit for my work. And a bonus is great, and I love positive feedback!!

Good luck and holler at me if you need annything!

My Best------------------

Customer: replied 6 years ago.
Relist: Inaccurate answer.
I have tested positive for benzodiazepine in a police urinalysis but I am not taking a benzodiazepine drug - how can this be?
(I am currently taking Prozac & Oxycontin & Oxynorm & Nabilone for chronic back pain.)
I would really appreciate your opinion.
Expert:  Dr. Lori replied 6 years ago.

Hello again---

If the police did an immediately reported test, and ths was positive for BENZO, there are a few other drugs that can cause this. If you have had none of these listed in my previous answer, then the Police's test may be Wrong!!!!!!

The urine needed to be sent to a lab for a further special test. That test doesn't measure BENZOS altogether, but the exact amount of each drug. If they did that test, which they must do to hold up in courts, etc,,, It will show BENZO NEGATIVE.

That test requires the urine to be sent to a special lab, and if you took no BENZOS, it will be NEGATIVE.

Do you see what I am saying?

You could have the confirmation test, and it should be NEG!

So--- the urine test the police did would then be WRONG! That would be good!

so--- they must have sent your urine out to be tested again...that is the result you need!

Did your urine test + for OXY ? It should have. If it didn't, maybe the urines got mixed up there, and the urine belonged to someone else.

So-- either the test is wrong, and you need to have a urine GC_MS test, or it was someone else's urine.

Please ask me anything if this is unclear.

My Best---

Customer: replied 6 years ago.
The test doesn't test for specific drugs here in Ireland !!
Is there a possibility putting all the drugs I am taking could cause a Benzo + result?
Expert:  Dr. Lori replied 6 years ago.

Hi again!

OK.....In Ireland huh? The tests used in the US that test + for a"drug class will not be the type of test that matters in the end. Tests that show "BenZO" positive are only preliminary tests. The test done to confirm these take a couple of days to return back, and would show "what" Benzo was possible. If these tests are not done in Ireland, and it is possible for Prozac to falsely make the urine to show a "+ BENZO", then comparng structures it is possible for Zoloft to do the same, theoretically.

Of course all of this depends on the test that you were subjected to, and its rate of false positivity. So, if they started with an ELIZA test, and this is only started by a phoned Rx to a local pharmacy, the next question is, DO they do confirmatory testing? This would be the one trying to measure the drug specifically.

Based on the tests historically, we have seen Fibromyalgia meds give a false Pos test. We have also seen Zoloft show a false +. Zoloft and Prozac are in the same drug class, So, it remains possible that Prozac is causing a false positive, yes.

Did they not send your test out to a lab for confirmation? If not, it is possible to have a false positive.

You need your test to be sent for a "confirmation test.' and this is also a standard in the US, and takes some time to get the result. You need to ask if they can hold the + urine, and sent it to the lab, for the " insane'' DRUGs of Abuse. PACKAGE.

Customer: replied 6 years ago.
Dear Dr Lori
Many thanks for your reply.
My sample was sent to confirmation lab.The result comes back + or -. I will not be informed of levels or which Benzo was present in the sample taken. How long do labs keep urine samples for? I am concerned that I have tested + Benzo and I am not taking a Benzo. I am taking Nabilone & Prozac & Oxycontin & Oxynorm.
If I plead guilty to this charge I am facing a mandatory 3 years driving disqualification !!!! I need to be very sure of my facts if I oppose the charge plus it will be hugely expensive to prove that I am not guilty. All the medication I am taking are prescribed by my doctor.
I look forward to you or anybody elses thought on this matter.
Kind Regards
Expert:  Dr. Lori replied 6 years ago.


I have a few thoughts and ideas which I am happy to share, but in all fairness, I need to request that you accept any of my previous answers first. I have spent a good deal of time working with you, and receive no credit until you click "ACCEPT". This does not end our communication in any way, and the question remains open and unchanged because of this. Also, you are not charged for accepting an answer, as your deposit has already been paid to JA. Accepting an answer mearly allocates that deposit to your answering provider upon your accept. I appreciate your response to this and will respond to your concerns there after.

Thank you and hope to hear from you soon!

Expert:  Family Physician replied 6 years ago.
There are a number of medications that have been shown to cause false positive drug tests for the benzodiazepines. None of the drugs that you listed have been documented to cause false positives.

A number of the anti-inflammatory medications including fenoprofen, flurbiprofen, indomethacin, ketoprofen, and tolmetin have been reported in medical journals to cause false positive on certain brands of screening drug tests for benzodiazepines.

I don't know if any of these particular medications are available in Ireland (and if you might have used them for a headache or some other pain before the test)

You may wish to speak with your attorney who is representing you in this matter to see if a hair test with GC/MS confirmation (which has a detection period of approximately 90 day) would be acceptable as evidence to refute this urine drug test.
Family Physician, Board Certified MRO
Category: Drug Testing
Satisfied Customers: 12816
Experience: Medical Review Officer - Physician Trained and certified in drug test interpretation
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