Hair Follicle and B12 False + for THC?

Long Term Care Columnist / Guide · Jul 4, 2018

Hi there, and Welcome to Allnurses!

While I personally can't answer your questions, I'd like to invite you to check out our Nurses and Recovery forum, where members who are experienced in these things can give you some ideas.

Best wishes,

Viva

Kallie3006, ADN · Jul 4, 2018

False positives can occur in a hair test, but when a positive shows up the sample must be confirmed with a GC/MS,gas chromatography/mass spectrometry. Each drug comes off the GC at a certain time (retention time) and with a specific amount of ions ratio, that allows it to be separated and distinguished from similar substances. To be a confirmed positive the sample must match an established pure standard of the drug in both retention time and ion ratios. Also the hair follicle will show up positive for the drug as well as the metabolite that is created when the body breaks down the drug. ie: cocaine users will show positive for cocaine AND the metabolite, benzoylecgonine.

Hope this helps!

smitherboy82 · Jul 4, 2018

So do you think I should be fine on passing the hair follicle test since its vitamins and not THC from a real joint.

Kallie3006, ADN · Jul 4, 2018

It should be ruled out with the GC/MS confirmation but I would disclose the medications you are taking

smitherboy82 · Jul 4, 2018

That is what worries me. Its not B2 from any medications its from a hair supplement that I am taking. So I dont know if they will count it as a false positive

Kallie3006, ADN · Jul 4, 2018

A supplement is considered a medication and would need to be disclosed for the chance it does cause a false positive. Supplements also need to be disclosed to your doctor if you get put on any RX d/t many interactions that can occur with different medication combos.

If you are afraid this would cause a false positive and don't want to chance it, I would stop taking it, although the follicle test can date back 3 months. Riboflavin will not provide a means of explaining a positive THC that is confirmed with GC/MS and a MRO validation.

smitherboy82 · Jul 5, 2018

Thank you for the information and easing my mind. I really appreciate it.

DO you personally think that the B2 Riboflavin would even show up on a hair follicle? I only took 2mg (from a prenatal) one day, 2mg another day(prenatal) and 5mg another day(was an ingredient in the extra strength hair vitamin) (all within a week)

Clean&SereneRN · Jul 5, 2018

I take a B12 among many other supplements daily and have never had a false positive for them in an entire year of monitoring. My chain of custody forms that I fill out (my state uses FirstLab) requires that you list all medications taken in the past 72 hours, so I am always sure to include my supplements. I think you are fine but I know the feeling of being nervous like you are! Breathe easy!

Bonstemps, EMT-P · Jul 5, 2018

If you do run + (we can't say for sure, friend, sorry), ask for a secondary test.

smitherboy82 · Jul 5, 2018

Thank you for that information. I am mainly worried about the B2. I plan on calling the testing facility tomorrow and asking them personally if it will show up

Kallie3006, ADN · Jul 5, 2018

I wish I could say "No, you will be fine", but unfortunately I do not know for sure. The one good thing that you have on your side is the test is a hair follicle which covers a broader time span that urine, saliva or blood. If by some chance it does come back + you can get another test completed from a separate source and it will still cover the time frame the original test does since the hair can show the previous 2-3 months and you have possibly a wk lapse from testing sample taken to results. I'm sorry I can't provide any better ease for you