Trends in Urine Drug Monitoring Among Persons Receiving Long-Term Opioids and Persons with Opioid Use Disorder in the United States.

BACKGROUND: Practice guidelines recommend urine drug monitoring (UDM) at least annually in the setting of chronic opioid therapy as an objective assessment of substance use. However, empirical evidence on who gets tested and how often testing occurs is lacking. OBJECTIVES: This study investigates 10-year UDM trends in the United States based on 2 factors: (1) the duration of prescription opioid treatment, and (2) having an opioid use disorder (OUD) diagnosis and medications for opioid use disorder (MOUD) prescriptions. STUDY DESIGN: Observational cross-sectional study. SETTING: Research was conducted using administrative claims data from Optum's deidentified Clinformatics Data Mart Database for the period 2007 to 2016. The dataset contained information on the plan enrollment and health care claims from 50 states and the District of Columbia. METHODS: To examine trends in UDM based on the duration of prescription opioid treatment, persons receiving prescription opioid analgesics were categorized into 4 groups based on the number of days covered: (a) less than 90 days, (b) 90 to 179 days, (c) 180 to 269 days, and (d) at least 270 days. To examine trends based on an OUD diagnosis and MOUD prescriptions, persons diagnosed with OUD were identified and categorized based on the presence of MOUD prescriptions as follows: (a) OUD with buprenorphine (BPN) and naltrexone (NTX) in the same year; (b) OUD with BPN only; (c) OUD with NTX only; (d) OUD with chronic prescription opioid analgesics (>= 90 days); (e) OUD without prescription opioid analgesics, BPN, or NTX; and (f) chronic prescription opioid analgesics (>= 90 days) without an OUD diagnosis. For analysis, the percent receiving UDM was estimated per group per year. Then the data were restricted to those receiving at least one UDM to estimate the average number of UDM per person. RESULTS: Data included an average of 364,485 persons per year receiving prescription opioid analgesics for chronic use, and 10,277 per year receiving an OUD diagnosis. Among those receiving prescription opioid analgesics, less than 50% received UDM. For those receiving at least one UDM, one additional UDM was performed per person as the duration of opioids increased by 90 days. Among persons with OUD, the percent receiving UDM was the highest for those receiving both BPN and NTX (87%), followed by those receiving BPN only (80%), chronic opioids (79%), NTX only (72%), and those not receiving any MOUD/opioids (54%). LIMITATIONS: Methadone dispensing for OUD treatments was not captured in administrative claims data. CONCLUSIONS: Although recommended for patients with chronic pain, UDM is provided less than half of the time for these patients. However, once patients received at least one UDM, they would continue to receive it on a fairly regular basis. Compared with those with chronic pain, persons diagnosed with OUD are more likely to receive UDM at a more frequent interval.

Naltrexone and Its Noroxymorphone Minor Metabolite - A Case Report.

As part of substance use maintenance programs, individuals are monitored for sobriety through urine drug screens. A positive screen, and its confirmation and interpretation, can have devastating consequences, sometimes even leading to termination from the program and relapse. Naltrexone metabolism involves several steps and metabolites - one minor metabolite with very little mention in medical literature being noroxymorphone. This is also the final intermediate in the metabolic pathway of oxycodone; hence, detection is naturally presumed by clinicians to be attributed to oxycodone use. Through this case report, we alert clinicians that, depending on individual pharmacogenomics, it is possible to obtain a positive confirmation of this component alone (without any oxycodone pathway intermediates) with naltrexone administration.

Circumstances of death of opioid users being treated with naltrexone.

BACKGROUND AND AIMS: Naltrexone is an opioid antagonist used as a maintenance drug for the treatment of opioid dependence and in opioid withdrawal regimens. The current study aimed to: (1) determine the clinical characteristics and circumstances of death of people undergoing naltrexone treatment for opioid dependence; and (2) determine the blood toxicology of cases including naltrexone concentrations, the presence of other drugs and a comparison of morphine concentrations in the presence and absence of naltrexone. DESIGN: Retrospective study of all deaths among people undergoing naltrexone treatment for opioid dependence retrieved from the National Coronial Information System, 2000-17. SETTING: Australia-wide. CASES: Seventy-four cases, with a mean age of 32.5 years; 81.1% male. MEASUREMENTS: Information was collected on demographics, manner of death, naltrexone treatment history, toxicology and major organ pathology. FINDINGS: Death was attributed to opioid toxicity in 86.5% of cases: accidental (79.7%), deliberate (6.8%). In 55.4% of all cases the decedent was maintained on oral naltrexone and 32.4% had a recent naltrexone implant. In five cases the decedent was undergoing opioid detoxification. Among those screened for naltrexone, naltrexone was present in the blood or urine of 52.5% (15.8% of oral maintenance cases, 85.7% of implant cases). Fourteen cases were known to have died from opioid toxicity with naltrexone present in their blood or urine. The median blood naltrexone concentrations were within the reported therapeutic range. CONCLUSIONS: The primary cause of death among people undergoing naltrexone treatment for opioid dependence in Australia from 2000 to 2017 was opioid toxicity, the majority of cases having been maintained on oral naltrexone. Cases in which naltrexone was not detected indicate the importance of treatment compliance. Deaths due to opioid toxicity where naltrexone was present indicates the possibility of overdose while naltrexone medication is maintained.

Computation-Assisted Molecularly Imprinted Polymer Synthesis for Extraction of Naltrexone from Urine Using Experimental Design and Determination by UPLC-DAD.

To design a molecularly imprinted polymer (MIP) for naltrexone, calculations were performed using Gaussian 03 software, and the interaction energy (ΔE) of template-monomer complexes was estimated using the density functional theory method with the B3LYP function and 6-311G (d) basis set. The effect of different solvents in the polymerization process was studied using the polarizable continuum model. It was shown that five molecules of methacrylic acid gave the largest ΔE with tetrahydrofuran as the polymerization solvent. Effective factors of the removal efficiency of naltrexone by the MIP were selected using a central composite design, and thereafter, the optimization of significant factors was performed by response surface methodology. The results predicted through these models showed good agreement with experimental values. The adsorption amount, selectivity distribution coefficient, and selectivity coefficient were found to be 11.60 mg/g, 35.31, and 2.27, respectively. Experiments of naltrexone adsorption onto the MIP were in accordance with the first-order and Langmuir-Freundlich adsorption models. By applying the data to the Scatchard equation, the KD and Qmax were determined as 526.31 mg/L and 19.47 mg/g, respectively.

Employment-based reinforcement of adherence to oral naltrexone in unemployed injection drug users: 12-month outcomes.

Oral naltrexone could be a promising relapse-prevention pharmacotherapy for recently detoxified opioid-dependent patients; however, interventions are often needed to promote adherence with this treatment approach. We recently conducted a study to evaluate a 26-week employment-based reinforcement intervention of oral naltrexone in unemployed injection drug users (Dunn et al., 2013). Participants were randomly assigned into a contingency (n = 35) group required to ingest naltrexone under staff observation to gain entry into a therapeutic workplace or a prescription (n = 32) group given a take-home supply of oral naltrexone and access to the workplace without observed ingestion. Monthly urine samples were collected and analyzed for evidence for naltrexone adherence, opioid use, and cocaine use. As previously reported, contingency participants provided significantly more naltrexone-positive urine samples than prescription participants during the 26-week intervention period. The goal of this current study is to report the 12-month outcomes, which occurred 6 months after the intervention ended. Results at the 12-month visit showed no between-groups differences in naltrexone-positive, opioid-negative, or cocaine-negative urine samples and no participant self-reported using naltrexone at the follow-up visit. These results show that even after a period of successfully reinforced oral naltrexone adherence, longer-term naltrexone use is unlikely to be maintained after reinforcement contingencies are discontinued. (PsycINFO Database Record

Naltrexone metabolism and concomitant drug concentrations in chronic pain patients.

Naltrexone is effective in treating opioid dependence by blocking µ, κ and δ opiate receptors. Naltrexone is mainly metabolized to an active metabolite 6ß-naltrexol by dihydrodiol dehydrogenase enzymes. Concomitant opioids will not be effective while patients are taking this antagonist. This was a retrospective analysis of urinary excretion data collected from patients being treated with pain between November 2011 and May 2012. Naltrexone, 6ß-naltrexol and concomitant opiate concentrations were measured by liquid chromatography-tandem mass spectrometry. Interpatient variability was calculated from first-visit specimens, and intrapatient variability was calculated from patients with two or more visits. Relationships of the metabolic ratio (MR; 6ß-naltrexol/naltrexone) with age, gender and urinary pH were also explored. From 88 first-visit patient specimens, the median MR was 3.28 (range 0.73-17.42). The MR was higher in women than men (5.00 vs. 3.14, P< 0.05). The MR showed no association based on age and urinary pH. Eighteen of 88 patients taking oral naltrexone tested positive for concomitant opiate use. Urinary MRs of 6ß-naltrexol/naltrexone were highly variable, which may contribute to variability in efficacy, toxicity and patient willingness to take naltrexone as directed. Twenty percent of patients tested positive for opiates and naltrexone, thus showing the importance of monitoring patients taking naltrexone.

Pulsed electromembrane extraction: a new concept of electrically enhanced extraction.

In the present work, pulsed electromembrane extraction (PEME) is introduced for the first time as an efficient and inexpensive method for the extraction of ionizable compounds from different matrices. The setup proposed for electromembrane extraction (EME) provides a very stable system and satisfactory repeatability (RSDs<4.4) in comparison with existing methods. In this paper, PEME is conducted for the extraction of model analytes from biological fluids. The effective parameters such as extraction time, applied voltage and the duration of pulse and outage period are optimized using the experimental design. Preconcentration factors in the range of 100-140 and recoveries in the range of 95-108 were obtained in different biological matrices. The linear dynamic ranges of 5-200 ng mL(-1) (with correlation coefficient higher than 0.9955) and limits of detection of 1.0 ng mL(-1) were obtained for both of the drugs. The figures of merit of PEME were compared with the results from conventional EME, which proves the advantages of the proposed technique.

Low-voltage electrically-enhanced microextraction as a novel technique for simultaneous extraction of acidic and basic drugs from biological fluids.

In the present work, for the first time a new set-up was presented for simultaneous extraction of acidic and basic drugs using a recent novel electrically-enhanced microextraction technique, termed electromembrane extraction at low voltages followed by high performance liquid chromatography with ultraviolet detection. Nalmefene (NAL) as a basic drug and diclofenac (DIC) as an acidic drug were extracted from 24 mL aqueous sample solutions at neutral pH into 10 µL of each acidified (HCl 50 mM) and basic (NaOH 50 mM) acceptor solution, respectively. Supported liquid membranes including 2-nitrophenyl octyl ether containing 5% di-(2-ethylhexyl) phosphate and 1-octanol were used to ensure efficient extraction of NAL and DIC, respectively. Low voltage of 40 V was applied over the SLMs during 14 min extraction time. The influences of fundamental parameters affecting the transport of target drugs were optimized using experimental design. Under optimal conditions, NAL and DIC were extracted with extraction recoveries of 12.5 and 14.6, respectively, which corresponded to preconcentration factors of 300 and 350, respectively. The proposed technique provided good linearity with correlation coefficient values higher than 0.9956 over a concentration range of 8-500 µg L⁻¹ and 12-500 µg L⁻¹ for NAL and DIC, respectively. Limits of detection and quantifications, and intra-day precisions (n=3) were less than 4 µg L⁻¹, 12 µg L⁻¹, and 10.1%, respectively. Extraction and determination of NAL and DIC in human urine samples were successfully performed. In light of the data obtained in the present work, this new set-up for EME with low voltages has a future potential as a simple, selective, and fast sample preparation technique for simultaneous extraction and determination of acidic and basic drugs in different complicated matrices.