Hair Test For Cocaine - Interpreting Results (Top voted first)

Is it possible to test positive for Cocaine but negative for Benzoylecgonine on the same Hair Test?

On the first test, Cocaine was positive, but Benzoylecgonine was negative. It did not indicate the quantitation levels, but the cutoff for the the initial test level and the MS confirm test level was 300 pg/mg.

On the second test, the Screen cutoff was 500 pg/mg. Confirm cutoff was 50 pg/mg for Benzoylecgonine and 100 pg/mg for Cocaine. Quantitation for Benzoylecgonine was 99 pg/mg and showed positive. Quantitation for Cocaine was 821 pg/mg and showed positive.

If the Benzoylecgonine level is below the cutoff, how is the Cocaine level higher?

Can anyone point me in the right direction here or have any insight as to what would cause a positive test for cocaine but negative test for benzoylecgonine.

I have researched this site and find information about what might cause a false positive test for benzoylecgonine other than cocaine. In these cases, it seems that positive results were seen for both cocaine and benzoylecgonine, or just positive for benzoylecgonine which is normally what the test is searching for.

I am looking for a reason why cocaine would be positive and benzoylecgonine is negative. Are there any medical reasons that would cause a false positive for cocaine, but not show the benzoylecgonine? Are there external factors that could cause this, meaning he didn't ingest cocaine for it to be metabolized through the liver, but somehow it is getting picked up on a hair test?

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Benzoylecgonine is a metabolite of cocaine, and it is mandatorily present. It should be impossible to be positive on coke, but negative on benzoylecgonine. The only possibility I can think of, is contamination. Did you rub your head on a line? (just joking there, it's got to be a mistake somehow).

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The same thing happened to me when I ran a test through Omega Labs. Benzoylecognine 100 pg/ng and Cocaine 842 pg/ng. I took cocaine in May 2015 and took my test Feb 2016. How is this possible? Why does it show Cocaine so high? I thought they only tested for Benzoylecognine? Seems like it would be out of my system? Please let me know what answers you found out? Thanks!

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My hair test came back positive for cocaine (with 15000mg) and I haven't touched it since January 2018. I took the hair test on May 4th. How could this be? That level is on a chronic user level and even before I quit taking it I never was an everyday user.

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