Fast Metabolism of Drugs?

This might be odd but I’ve researched and researched and can’t find much info.  I’ve been on Clonazepam for about a decade now (started my taper about a month ago). I’ve obviously always had a prescription, and I’ve been on the same daily dose.  Over the past decade I’ve had drug tests (urine) for various jobs. I always show the lab my prescription.  But literally EVERY time I test negative for Benzos.  One time I think I’d even taken one shortly before my test. Still tested negative.  Never thought much of it other than finding it odd.  We moved to CO a few months ago and for at least the last month, I’ve used some cannabis on a daily basis.  I’m beginning to job hunt so out of curiosity I bought at-home 10 panel drug tests and took two today. Both of them were negative for both Benzos and THC. Again, I take Clonazepam daily AND  stopped all cannabis  use only 2 days ago.  HOW in the world am I testing negative for these things?  Has anyone heard of such a thing? 

 

So now I’m wondering if I metabolize meds/drugs super quickly.  I do now know that I’ve been dealing with tolerance withdrawal(and/or inter dose withdrawals) for years(which is why I’m coming off of them).  But I wonder if I’m metabolizing this stuff so quickly, how might that affect my taper and withdrawal experience?    I’m just thinking out loud here.  Any thoughts as to why drug levels of drugs I use daily  are undetectable in my system? 

My main benzo experiences are with Diaz (long half life) and Xanax (short half life). From what I understand, the testing equipment varies greatly depending on make and model. When I worked on a Canadian provincial drug enforcement policy about 15 years ago, some of the testing equipment was frankly terrible. Progress has made leaps and bounds since then, but some kit on the market is still terrible for certain drugs. And it varies greatly depending on type of benzo too. Blood tests are the gold standard.

According to the following sources, immunoassays typically used for benzodiazepine urine drug screening are prone to false-negative results, especially in the case of clonazepam.

 

Negative Urine Drug Screen in a Patient with Chronic Benzodiazepine Use (2006)

https://www.proceedings.med.ucla.edu/wp-content/uploads/2016/11/A160818NG-WH-edited.pdf

 

Urine Drug Screening: Minimizing False-Positives and False-Negatives to Optimize Patient Care (2016)

https://www.uspharmacist.com/article/urine-drug-screening-minimizing-false-positives-and-false-negatives-to-optimize-patient-care

 

Urine Drug Tests: Ordering and Interpreting Results (2019)

https://www.ncbi.nlm.nih.gov/pubmed/30600984

 

Improved Clinical Sensitivity of a Reflexive Algorithm to Minimize False-Negative Test Results by a Urine Benzodiazepine Immunoassay Screen (2018)

http://jalm.aaccjnls.org/content/jalm/2/4/555.full.pdf