False-positive urine phencyclidine immunoassay screen result caused by interference by tramadol and its metabolites

Binh T Ly1, Stephen L Thornton, Colleen Buono

  • 1Division of Medical Toxicology, Department of Emergency Medicine, University of California, San Diego, San Diego, CA, USA. bly@ucsd.edu

Annals of Emergency Medicine
|September 20, 2011
PubMed

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