OBJECTIVES: Using the pentylenetetrazol (PTZ) discrimination assay, this study aims to investigate the effects of MG in responding to the PTZ stimulus and to assess the generalisation effects of withdrawal from MG to the PTZ stimulus.
METHODS: Rats (n = 20) were trained on a tandem (FR-10, VI-15) schedule of food reinforcement to press one lever after administration of the anxiogenic compound PTZ (16 mg/kg, i.p.) and an alternate lever after vehicle. Following acute tests, training was suspended, and rats were chronically treated with MG or morphine at 8-h intervals for 9 days and withdrawal was precipitated on the tenth day using naloxone (1 mg/kg, i.p.). The rats were tested for generalisation to PTZ at 2, 8 and 24 h after the last dose of MG or morphine administration.
RESULTS: Unlike morphine that produced dose-related PTZ-like stimulus, MG at 3, 10, 30 and 45 mg/kg doses showed no substitution to the PTZ discriminative stimulus. In contrast to morphine which produced a time-dependent generalisation to the PTZ stimulus, naloxone did not precipitate withdrawal effects in MG-treated rats as they selected the vehicle lever at three withdrawal time points.
CONCLUSION: These results demonstrate that MG produces a very different response to morphine withdrawal that is not associated with anxiogenic-like subjective symptoms. These characteristics of MG may provide further support for use as a novel pharmacotherapeutic intervention for managing opioid use disorder.
DESIGN: A 2 × 2 factorial, repeated-measures, open-label, randomized clinical trial.
SETTINGS: General medical practice offices in Muar, Malaysia.
PARTICIPANTS: Opioid-dependent individuals (n = 234).
INTERVENTIONS: Participants were randomly assigned to one of four treatment conditions and received study interventions for 24 weeks: (1) physician management with or without behavioral counseling and (2) physician management with or without abstinence-contingent buprenorphine-naloxone (ACB) take-home doses.
MEASUREMENTS: The primary outcomes were proportions of opioid-negative urine tests and HIV risk behaviors [assessed by audio computer-assisted AIDS risk inventory (ACASI-ARI)].
FINDINGS: The rates of opioid-negative urine tests over 24 weeks of treatment were significantly higher with [68.2%, 95% confidence interval (CI) = 65-71] than without behavioral counseling (59.2%, 95% CI = 56-62, P
Objective: This study addressed the therapeutic effect of 3-(2,5-dimethoxyphenyl)-1-(5-methyl furan-2-yl) prop-2-en-1-one (DMPF-1); synthetic chalcone derivative, on antinociceptive activity in vivo.
Materials and Methods: The antinociceptive profile was evaluated using acetic-acid-induced abdominal writhing, hot plate, and formalin-induced paw licking test. Capsaicin, phorbol 12-myristate 12 acetate (PMA), and glutamate-induced paw licking test were carried out to evaluate their potential effects toward different targets.
Results: It was shown that the doses of 0.1, 0.5, 1, and 5 mg/kg of DMPF-1 given via intraperitoneal injection showed significant reduction in writhing responses and increased the latency time in hot-plate test where reduced time spent on licking the injected paw in formalin and dose contingency inhibition was observed. The similar results were observed in capsaicin, PMA, and glutamate-induced paw licking test. In addition, the challenge with nonselective opioid receptor antagonist (naloxone) aimed to evaluate the involvement of the opioidergic system, which showed no reversion in analgesic profile in formalin and hot-plate test.
Conclusion: Collectively, this study showed that DMPF-1 markedly inhibits both peripheral and central nociception through the mechanism involving an interaction with vanilloid and glutamatergic system regardless of the activation of the opioidergic system.
METHODS: Participants with opioid and ATS dependence (N = 69) were enrolled in a pilot, double-blind, placebo-controlled randomized clinical trial; all received buprenorphine/naloxone and behavioral counseling and were randomized to atomoxetine 80 mg daily (n = 33) or placebo (n = 33). The effect size of the between-group difference on the primary outcome, proportion of ATS-negative urine tests, was estimated using Cohen's d for the intention-to-treat (ITT) sample and for higher adherence subsample (≥60 days of atomoxetine or placebo ingestion).
RESULTS: Participants were all male with mean (SD) age 39.4 (6.8) years. The proportion of ATS-negative urine tests was higher in atomoxetine- compared to placebo-treated participants: 0.77 (0.63-0.91) vs. 0.67 (0.53-0.81, d = 0.26) in the ITT sample and 0.90 (0.75-1.00) vs. 0.64 (0.51-0.78, d = 0.56) in the higher adherence subsample. The proportion of days abstinent from ATS increased from baseline in both groups (p
OBJECTIVE: The International Survey Informing Greater Insights in Opioid Dependence Treatment (INSIGHT) project aimed to assess aspects of OMT access and quality of care by surveying patients and users with opioid dependence, and healthcare professionals treating opioid-dependent patients.
MATERIALS AND METHODS: Using a structured questionnaire, 50 patients who were currently receiving OMT (or had received OMT in the past 3 months) and 77 physicians were surveyed in Malaysia regarding the provision and quality of OMT.
RESULTS: Patients were predominately male and in their thirties. Nearly all patients (98%) reported currently receiving methadone liquid; almost half (48%) reported ever having received psychosocial counselling and only 14% had ever received buprenorphine-naloxone in the past. Most physicians reported they were treating their patients with OMT (77% on methadone and 15% on buprenorphine-naloxone), and 3% used psychosocial counselling alone. Although methadone maintenance doses were close to levels recommended by WHO guidelines, induction doses of methadone, and both induction and maintenance doses of buprenorphine were well below these levels in Malaysia.
CONCLUSIONS: The findings suggest that OMT implementation in Malaysia can be improved by providing patients with more education on treatment options, better access to available treatments, including abuse-deterrent formulations, and psychosocial support.