False-Positive Urine Screening for Benzodiazepines: An Association with Sertraline?: A Two-year Retrospective Chart Analysis.
OBJECTIVE
To determine the frequency of false-positive benzodiazepine screens associated with sertraline use at the authors' institution.


METHODS
Urine drug screen results spanning a two-year period were data mined to identify those positive for benzodiazepines. When confirmatory gas chromatography-mass spectrometry determined false positives, they were subsequently cross-referenced against pharmacy records to identify patients with active prescriptions for sertraline at the time of the initial urinary drug screen.


RESULTS
Of the 522 records reviewed, 160 were later determined to be false positives by confirmatory gas chromatography-mass spectrometry. Sixty-two of those were associated with a concomitant benzodiazepine prescription. Of the 98 remaining, 26 were associated with a concomitant sertraline prescription.


CONCLUSIONS
Our findings suggest that sertraline may be an unreported cause of false-positive benzodiazepine results in a widely used screening assay.
Nasky
Kevin M
KM
Dr. Nasky is Staff Psychiatrist, Department of Psychiatry, Naval Medical Center, Portsmouth.
Cowan
George L
GL
Knittel
Douglas R
DR