Standard urine drug screens can be false-negative for some benzodiazepines

Question from a Member: What about when a patient has been prescribed a benzodiazepine (or given a benzodiazepine in a controlled setting), and yet their urine drug screen does not come up positive for benzodiazepine? This always mystifies me. To understand why some urine drug screen results may not be positive for benzodiazepines even though…