[Arm89]

Hello all,

I had done a lot of research about Urine Drug Testing since I had taken one for new job. I was concerned because I used Benzocaine ointment on a canker sore 2 and 3 days prior to the test. I’m afraid of a false-positive for Cocaine. According to my research, it should NOT cause a false-positive since Benzocaine is structurally different from Cocaine and it’s metabolites.

However, reading comments on various articles show that people have had false-positives from topical anesthetics. Such are listed below:

https://www.chemicalforums.com/index.php?topic=2456.0

https://cen.acs.org/articles/87/i47/Drug-Testing-CaineDrugs.html

I am a little reassured by page 13 of this article on right hand side:

https://www.mayoclinicproceedings.org/article/S0025-6196(16)30825-4/pdf

However, given all these comments of people who have had practical differences from what the science shows...do I have reason to worry?

Thanks in advance!