Ibudilast, a nonselective phosphodiesterase inhibitor, is used clinically in Asia for the treatment of asthma and poststroke dizziness. Recent preclinical studies have suggested that it also inhibits glial cell activation in rodents, and may alter opioid-mediated effects, including analgesia and withdrawal symptoms. The effects of ibudilast on the abuse potential of opioids in humans are largely unknown. The present study was designed to examine the influence of ibudilast on subjective (including drug craving), reinforcing, and analgesic effects of oxycodone in human volunteers diagnosed with opioid dependence (equivalent to moderate-severe opioid use disorder). Non-treatment-seeking opioid-dependent male volunteers (n=11) underwent an in-patient detoxification with morphine, followed by maintenance on placebo (0 mg b.i.d.) and active ibudilast (50 mg b.i.d.). Under each maintenance dose, six experimental sample and choice sessions were completed involving oral oxycodone administration (0, 15, and 30 mg/70 kg, p.o.). Subjective effects of oxycodone and drug craving were measured with visual analog scales (VAS) and a Drug Effects Questionnaire. The cold pressor test was used to produce pain, and a modified progressive-ratio choice procedure was used to measure the reinforcing effects of oxycodone. Under the active ibudilast condition compared with the placebo condition, ratings of drug liking following 15 mg of oxycodone were decreased significantly. The mean drug breakpoint value was also significantly lower in the active vs the placebo ibudilast condition under the 15 mg oxycodone condition, but not significantly lower under the 30 mg oxycodone condition. Heroin craving was significantly reduced under active ibudilast vs placebo, and similar effects were observed for tobacco and cocaine craving. Furthermore, mean subjective ratings of pain were lower in the active ibudilast condition. Our data suggest that ibudilast may be useful for treating opioid use disorders and it may enhance the analgesic effects of oxycodone.

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Objectives Many adolescents and young adults report having chronic pain. Urine drug toxicology (UDT) is not routinely used in the pediatric pain management population, despite more routine use in adults with pain, particularly those prescribed opioids. As a first step toward establishing monitoring practices in pediatric and adolescent pain management, the present study evaluated the role of UDT in conjunction with a standard clinical interview in identifying the rate of adherence to an established analgesic regimen. The study also aimed to assess the use of UDT in identifying possible aberrant behaviors in this population. Methods Data were acquired from a convenience sample of 50 pediatric and adolescent pain management initial consultations, during which a clinical interview and UDT were conducted. Data were analyzed to determine adherence to an established analgesic prescription regimen, and for identification of aberrant behaviors including concurrent use of illicit substances and prescription medication misuse. Other pertinent demographic and clinical factors were examined as factors in adherence. Results Opioid medications were prescribed for 42% of the sample receiving pain medications, and 22% of the sample was nonadherent to their prescription analgesic regimen. Factors associated with a higher likelihood of nonadherence were an older age and having an opioid prescription. The majority (90%) of those nonadherent to their analgesic regimen displayed some form of aberrant behavior. Among the nonadherent patients, 50% were identified by UDT alone, and 50% were identified by self-report during the clinical encounter. Conclusions These results highlight the challenges of identifying nonadherence to a prescription regimen among adolescents with chronic pain. In addition, this preliminary work suggests that UDT could be used in conjunction with careful clinical interviewing to substantiate patient report and increase the likelihood of detecting analgesic nonadherence and aberrant behaviors.

Background Extended-release buprenorphine (XRB) offers a novel approach to sustained monthly treatment for people who use opioids in criminal justice settings (CJS). This study explores the experiences of adults receiving XRB as a jail-to-community treatment. Methods and findings In-depth qualitative interviews were conducted among adult participants with opioid use disorder (OUD; n  = 16) who were recently released from NYC jails and maintained on XRB after switching from daily sublingual buprenorphine (SLB). Interviews elaborated on the acceptability and barriers and facilitators of XRB treatment pre- and post-release. Interviews were audio recorded, transcribed, and analyzed for content related to factors influencing XRB treatment uptake and community reentry. Important themes were grouped into systems, medication, and patient-level factors. Key systems-level factors influencing initiation of XRB in jail included an alternative to perceived stigmatization and privacy concerns associated with daily in-jail SLB administration and less concerns with buprenorphine diversion. In-jail peer networks positively influenced participant adoption of XRB. XRB satisfaction was attributed to reduced in-jail clinic and medication administration visits, perceived efficacy and blockade effects upon the use of heroin/fentanyl following release, and averting the risk of criminal activities to fund opioid use. Barriers to retention included post-injection withdrawal symptoms and cravings attributed to perceived suboptimal medication dosing, injection site pain, and lack of in-jail provider information about the medication. Conclusion Participants were generally favorable to XRB initiation in jail and retention post-release. Further studies are needed to address factors influencing access to XRB in criminal justice settings, including stigma, ensuring patient privacy following initiation on XRB, and patient-, provider-, and correctional staff education pertaining to XRB. Trial Registration ClinicalTrials.gov Identified: NCT03604159.