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Will Flexeril show up on a routine urine tox screen?

This question has also been asked and answered here: Will Flexeril (cyclobenzaprine) show up on a drug test?

Responses (11)

Inactive 16 Jul 2010

Flexaril is simply a muscle relaxent just like many people think soma is a narcotic because it has the potencial for addiction. NO it will not show up as anything on a UA(tox screen). Hope this was helpful have a good day!

joeblue 6 Jan 2012

You are wrong sir as i have said to the doc, flexeril is a member of the tricyclic antidepressant family,and many test panel and lab test for this on a reg. Sorry to burst your bubble

J4go 18 Apr 2014

JohnBlue is dead wron it does not belong to the tricyllic or any other anti-depressant family.

toxmd 16 Jul 2010

MD toxicologist to the rescue.
Answer: NO
Flexeril will not show up on a urine toxicology screen.
If this answer is helpful, please indicate such.
God bless

joeblue 6 Jan 2012

Excuse me Dr. I must disagree, Flexeril will show up as a tricyclic antidepressant. As many drug test now a days test for. You yourself should know this as being a toxicoligist MD, Flexeril branches off the tricyclic antidepressant family. I don't mean to be disrespectful or anything.

emmarosewrites 24 Aug 2012

Doc this is not to you, but to the person who insists that they will show up on a drug test.
I'm confused, why would an employer care about tricyclic antidepressants? If a screen showed up for any antidepressant, I'm sure that would not prohibit someone from obtaining employment. I think someone is missing the point here.

Plus, most employers don't do that sort of test. If they are testing specifically for antidepressants, then one could show up, but the typical pre-employment drug screen tests for the following: Cocaine, Marijuana, Opiates, Methamphetamines, Benzodiazepines with the possibility of testing for Phencyclidine, Oxy, or Meth specifically.

christineATU 19 Jul 2010

Both answers are correct. But also remember, there are spaces on the Ameritox form (one of several testing labs) where the tester can write in any medication the person paying for the test wants you tested for. There are also boxes they can check off (suboxone is one of them) if they want you tested for it. It all depends on how much money the test requester wants to pay and if they think you may be taking something other than the standard drugs they normally test for. Bottom line... most people do not want to pay for the more in depth testing. So I wouldn't worry at all.

christineATU 19 Jul 2010

I know mrspage is tired of reading this but I thought you might find this interesting...

"Statistical Information About Drug Testing and Passing Drug Tests"
Provided by HealthTech Inc.

According to R. Brookler, "Industry Standards in Workplace Drug Testing," Personnel Journal, (April 1992). Laboratories admit that urine tests are not always accurate. The manufacturers of all drug testing equipment acknowledge that all positive results should be confirmed with a more sophisticated test. The only acceptable drug confirmation test is the costly gas chromatography/mass spectrometer. Without confirmation by an alternative testing method, urine drug tests are not sufficiently reliable to hold up in court.

Inactive 19 Jul 2010

Yes i remember chris where were you when i needed you i cant remember all of that by memory lady.

miamivirgo918 28 Aug 2013

I just took a probation drug test and I had took 2 flexeril last night and today before before the test. It DID NOT show up ;-)

mudplayerx 26 Feb 2014

I work in a hospital lab as a MLS (medical laboratory scientist). You have to understand the testing before you can ask or answer this question.

First of all, there is qualitative (screen) tests and quantitative tests that not only give a positive or negative result, but an amount detected. The quantitative tests are the only ones usuable for legal cases such as court cases, probation, or pain clinic compliance.

The qualitative tests are mainly used in hospital ERs and in pre-employment drug screens. They are highly sensitive but not very specific, so false positives are common. They come in different kits that tests for different drugs. You may get lucky and not get tested for the drug you are abusing.

Mike Curtis 13 Dec 2014

What does anything you posted have to do with Flexeril. You of all people should know that muscle relaxers are not tested for on 10 panel or any other panel drug screen. Nor would it should if/when sent off to GC/MS.

cooperslady 21 Sep 2014

I was just prescribed flexeril for a pinched nerve in my back. I do weekly drug screens for my doctor. And antidepressants showed up in my test. After my urine was dent to a lab, it came back as my prescribed flexeril. So yes it does show up in a test. But its non-narcotic. It falls under category of antidepressants.

Mike Curtis 13 Dec 2014

No... it doesn't. Stop spreading misinformation.

mudplayerx 10 Jan 2018

Mike, Flexeril is a common cross reactant with TCA’s in drug tests. I think you are the one that should stop providing misinformation.

jdaum 4 Jan 2015

According to the Medscape app under flexeril and the pharmacology tab it states:

"Structurally related to cyclic antidepressants, and pharmacologic effects are similar, including reserpine antagonism, norepinephrine potentiation, potent peripheral and central anticholinergic effects, and sedation; reduces tonic somatic motor activity influencing alpha and gamma motor neurons"

This leads me to believe you could get a false positive for tricyclic antidepressants, which are potentially fatal if overdosed...

Barb0109 4 Nov 2016
Toisoldier2000 2 Jun 2017

I just took flexeril. I tested myself with 12 panel and it is positive for barbiturates

Punk1234 12 Jun 2017

This makes no sense, it's not even close to a barbiturate. Lol. (Xanax, Ativan, clonopin). So you were certainly doing something else with it lol...


Xannax valium clonipin versed Ativan and such are benzodiazipeims not barbiturates had to clear that one up

masso 2 Jun 2017

Just to educate not judge:

Flexeril (Cyclobenzaprine) belongs to the drug of class skeletal muscle relaxants.

Cyclobenzaprine – Can Cause False Positives For Tricyclic Antidepressants

I know it for a fact.-

Regards, masso.-

masso 2 Jun 2017


" Several other substances also cause false-positive tricyclic antidepressant toxic screen results, including certain antipsychotic medications, antihistamines, and the muscle relaxant cyclobenzaprine. Specific tests and drugs causing false-positive results are presented in table form."

SOURCE: National Institute of Health.-US Library of Medicine.

Rowdy Ron 9 Jan 2018

Lol, i guess this isn't the place to get answer's. Too many say yes, too many say no. Which one is it? free discount card

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