A preliminary study of hydrocodone and hydromorphone to oxycodone ratios for distinguishing impurities from independent opioid use.

BACKGROUND: Urine drug testing (UDT) monitors prescription compliance and/or drug abuse. However, interpretation of UDT results obtained by liquid chromatography-tandem mass spectrometry (LC-MS-MS) can be complicated by the presence of drug impurities that are detected by highly sensitive methods. Hydrocodone is a drug impurity that can be found as high as 1% in oxycodone pills. OBJECTIVES: We evaluated the frequency and concentration of hydrocodone and its metabolite, hydromorphone, in patients taking oxycodone to check if the ratio of hydrocodone or hydromorphone to oxycodone could distinguish between oxycodone only use from those consuming additional opiates. DESIGN & METHODS: We correlated LC-MS/MS results with medication records of 319 patients with positive oxycodone results over 7 months (4/2021-11/2021). RESULTS: Fifteen of 319 patients with positive oxycodone results were taking oxycodone only. For these 15 patients, the mean ratio of hydrocodone to oxycodone was 0.57% (range 0.05%-3.35%), and the mean ratio of hydromorphone to oxycodone was 0.81% (range 0.18-3.51%). CONCLUSIONS: Hydrocodone and/or hydromorphone are detectable in patients taking only oxycodone and can likely be identified as an impurity if their calculated ratio to oxycodone is <1 %. Further validation of the ratios in a larger sample size is recommended.

Direct analysis in real time mass spectrometry (DART-MS/MS) for rapid urine opioid detection in a clinical setting.

BACKGROUND AND AIMS: Current laboratory methods for opioid detection involve an initial screening with immunoassays which offers efficient but non-specific results and a subsequent liquid chromatography-tandem mass spectrometry (LC-MS/MS) confirmation which offers accurate results but requires extensive sample preparation and turnaround time. Direct Analysis in Real Time (DART) tandem mass spectrometry is evaluated as an alternative approach for accurate opioid detection with efficient sample preparation and turnaround time. MATERIALS AND METHODS: DART-MS/MS was optimized by testing the method with varying temperatures, operation modes, extraction methods, hydrolysis times, and vortex times. The method was evaluated for 12 opioids by testing the analytical measurement range, percent carryover, precision studies, stability, and method-to-method comparison with LC-MS/MS. RESULTS: DART-MS/MS shows high sensitivity and specificity for the detection of 6-acetylmorphine, codeine, hydromorphone, oxymorphone, hydrocodone, naloxone, buprenorphine, norfentanyl, and fentanyl in urine samples. However, its performance was suboptimal for norbuprenorphine, morphine and oxycodone. CONCLUSION: In this proof-of-concept study, DART-MS/MS is evaluated for its rapid quantitative definitive testing of opioids drugs in urine. Further research is needed to expand its application to other areas of drug testing.