2 doctors weighed in:
What would cause a false negative urine drug test for fentanyl patches?
2 doctors weighed in

Dr. James Cain
Internal Medicine - Nephrology & Dialysis
1 doctor agrees
In brief: Errors
1. Not wearing the patch, an exhausted patch, a placebo patch 2.
The test was not specific for fentanyl 3. Lab error 4. Specimen misidentification.

In brief: Errors
1. Not wearing the patch, an exhausted patch, a placebo patch 2.
The test was not specific for fentanyl 3. Lab error 4. Specimen misidentification.
Dr. James Cain
Dr. James Cain
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