Brief Answer:
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Detailed Answer:
Hello XXXXXXX
With increased urine testing, these false positives are becoming an increasing problem, because the basic test is not that accurate as you see.
I looked up several scientific articles on what can cause a false positive urine screen for benzodiazepines. Benzodiazepines are the class of medication that lorazepam is in.
The only thing that came up repeatedly as giving a false positive was the SSRI antidepressant sertraline, and also a particular NSAId (similar to ibuprofen).
So what to do: If the urine screen is inaccurate, the next step would be to get the more accurate GC-MS test done. I recommend you ask them to do this.
I'm sorry I couldn't pin point one of your medications with a research article to take to your doctor to back it up, but I can say that standard urine screens have their limitations and the next step is GC-MS.