Observation of improved adherence with frequent urine drug testing in patients with pain.

Objective: To determine the relationship between urine drug testing (UDT) frequency and patient adherence for prescribed buprenorphine, carisoprodol, fentanyl, hydrocodone, methadone, morphine, and oxycodone.

Setting: Patients with pain routinely seen by private practitioners.

Design: A retrospective analysis was conducted on urinary excretion data analyzed by Millennium Laboratories between March 2008 and May 2011.

Observations on the urine metabolic profile of codeine in pain patients.

This retrospective data analysis explored the relationship between codeine and its metabolites morphine, hydrocodone and hydromorphone. The objectives were: (i) to determine urine concentrations and mole fractions of codeine and metabolites and (ii) to examine the effect of cytochrome P450 (CYP) 2D6 inhibition on metabolite mole fractions. De-identified urine specimens were collected between September 2010 and July 2011 and analyzed using LC-MS-MS to determine codeine, morphine, hydrocodone and hydromorphone concentrations.

Observations on the urine metabolic ratio of oxymorphone to oxycodone in pain patients.

The object of this study was to evaluate the metabolism of oxycodone to oxymorphone in a pain patient population using a quantitative liquid chromatography-tandem mass spectrometry analysis of 32,656 urine specimens obtained from pain patients between March 2008 and Feb 2010. The observed excretion was modeled using logarithmic transformation and approximated a Gaussian distribution. Oxycodone excretion into urine had a geometric mean of 1.