title: The Disposition of Oxycodone and Metabolite in Human Hair.
abstract: The disposition of oxycodone (OC) and metabolites in hair remains poorly characterized. We present a case involving a pharmacist in an impaired professionals' monitoring program in whom hair testing yielded OC on two occasions. On both occasions, his hair was negative for the oxymorphone (OM) metabolite at the cutoff concentration of 100 pg/mg. He claimed that, absent the detection of metabolite, the OC necessarily represented external contamination. This prompted a review of the laboratory's OC-positive hair results for the quarter April-June 2014. Overall, 466 specimens contained OC, with a mean (median) concentration of 2,375 (1,060) pg/mg. Of these OC-positive specimens, only 47 (10%) contained detectable OM. When OC was present at or below the mean (median) concentration, only 2.2% (1.3%) of specimens were OM-positive. In the setting of OC administration, the detection of OM in hair is unlikely at a cutoff concentration of 100 pg/mg. More consistent demonstration of OC metabolite(s) in hair will require the validation of methods to detect OM at lower concentrations and/or methods to detect noroxycodone.
authors.affiliation: Divisions of Addiction Medicine, Pain Medicine, and Forensic Psychiatry, Department of Psychiatry, and the Florida Recovery Center, University of Florida College of Medicine, Gainesville, FL 32611, USA garyr@ufl.edu.
authors.forename: Gary M
authors.initials: GM
authors.lastname: Reisfield
authors.affiliation: United States Drug Testing Laboratories, 1700 S Mount Prospect Road, Des Plaines, IL 60018, USA.
authors.forename: Joseph T
authors.initials: JT
authors.lastname: Jones
mesh_terms: D004305:Dose-Response Relationship, Drug; D005069:Evaluation Studies as Topic; D006197:Hair / Q000737:chemistry*; D006801:Humans; D057230:Limit of Detection; D008297:Male; D009019:Morphinans / Q000032:analysis; D010098:Oxycodone / Q000032:analysis* / Q000737:chemistry*; D010111:Oxymorphone / Q000032:analysis; D015203:Reproducibility of Results; D013048:Specimen Handling; D015813:Substance Abuse Detection
chemical_list: D009019:Morphinans; C077256:noroxycodone; D010111:Oxymorphone; D010098:Oxycodone