LC-MS/MS Analysis of Urinary Excreted Pain Medications Offers Improved Patient Compliance, Detection of Diversion and Illicit Drug Use
Tue 11:30 AM - Track 1: Toxicology: Pain Management
Amadeo Pesce
Millennium Laboratories
Amadeo Pesce, Robert West, Bridgit Crews, Charles Mikel, Sergey Latyshev, Perla Almazan

Millennium Laboratories of California, Inc.
The application of liquid chromatography tandem mass spectrometry to the urine drug measurement of pain medications has permitted the use of 'dilute and shoot methods' which minimize sample preparation requirements, quantization over a 10exp4 range of values, and differentiation of parent drugs and their metabolites. The ability to quantify low concentrations of drug has shown that a significant number of chronic pain patients on opioid therapy have low but confirmed concentrations of these drugs and their metabolites. These more sensitive analyses help identify compliance for those patients on low medication dosages. These data suggest that the current practices of using immunoassay screening with Substance Abuse and Mental Health Services Administration SAMHSA cutoffs to define medication compliance are not appropriate for the clinical monitoring of the medications of pain patients. We propose screening and confirmation by LC-MS/MS at lower concentrations as the new standard. The ability of LC-MS/MS to quantify high concentrations of excreted drugs and their metabolites makes possible the identification of patients taking high dosages. This allows the laboratory to flag for physician review those patients on large prescribed doses as well as those possibly abusing their medications. The LC-MS/MS technology permits separation and determination of parent drugs and some of their metabolites. As a consequence, the laboratory can provide the practicing pain physician with more complete information on the excreted drugs and their metabolites, such as morphine and its metabolite, hydromorphone, oxycodone and its metabolite, oxymorphone. This in turn can help identify patients attempting to conceal drug diversion by ÒdippingÓ the parent medication in the test sample. Finally, the advent of Òdilute and shootÓ sample preparation has reduced the cost of analysis and these will soon be reflected in medical billing.