Drug dependence and abuse potential of tramadol.
(9/1183)
AIM: To assess the drug dependence and abuse liability of tramadol. METHODS: Subjects of opiate addicts with history of tramadol abuse were 219. Physical dependence of tramadol was assessed using opiate withdrawal scale (OWS), psychic dependence was assessed by association test of Addiction Research Center Inventory-Chinese Version (ARCI-CV); the degrees of craving experienced for tramadol was self-reported on visual analogue scale (VAS). RESULTS: The scores of OWS of tramadol were 0.05-1.07; 3 scores on scales in particular being used the identify euphoric effects--MBG, sedative effects--PCAG, and psychotomimetic effects--LSD of ARCI were 7.3, 6.1, and 3.4, respectively (F = 38.1, P < 0.01); 57.1% of tramadol abuse subjects had craving for tramadol (chi 2 = 75.86, P < 0.01). CONCLUSION: Tramadol produced high abuse potential among opiate addicts. (+info)
Functional dissociation of mu opioid receptor signaling and endocytosis: implications for the biology of opiate tolerance and addiction.
(10/1183)
Opiate analgesia, tolerance, and addiction are mediated by drug-induced activation of the mu opioid receptor. A fundamental question in addiction biology is why exogenous opiate drugs have a high liability for inducing tolerance and addiction while native ligands do not. Studies indicate that highly addictive opiate drugs such as morphine are deficient in their ability to induce the desensitization and endocytosis of receptors. Here, we demonstrate that this regulatory mechanism reveals an independent functional property of opiate drugs that can be distinguished from previously established agonist properties. Moreover, this property correlates with agonist propensity to promote physiological tolerance, suggesting a fundamental revision of our understanding of the role of receptor endocytosis in the biology of opiate drug action and addiction. (+info)
Methadone maintenance and state Medicaid managed care programs.
(11/1183)
Coverage for methadone services in state Medicaid plans may facilitate access to the most effective therapy for heroin dependence. State Medicaid plans were reviewed to assess coverage for methadone services, methadone benefits in managed care, and limitations on methadone treatment. Medicaid does not cover methadone maintenance medication in 25 states (59 percent). Only 12 states (24 percent) include methadone services in Medicaid managed care plans. Moreover, two of the 12 states limit coverage for counseling or medication and others permit health plans to set limits. State authorities for Medicaid and substance abuse can collaborate to ensure that appropriate medication and treatment services are available for Medicaid recipients who are dependent on opioids and to construct payment mechanisms that minimize incentives that discourage enrollment among heroin-dependent individuals. (+info)
A small area analysis estimating the prevalence of addiction to opioids in Barcelona, 1993.
(12/1183)
STUDY OBJECTIVE: To determine the distribution of opioid use prevalence in small areas and its relation with socioeconomic indicators. DESIGN: Capture-recapture was applied using data from the Barcelona Drug Information System for 1993 (treatment demands, hospital emergency room visits, deaths from heroin acute adverse reaction and pre-trial prison admissions). To avoid dependence between sources, a log-linear regression model with interactions was fitted. For small neighbourhoods, where capture-recapture estimates were not obtainable, the Heroin Problem Index (HPI) was used to predict prevalence rates from a regression model. The correlation between estimated opioid use prevalence by neighbourhoods and their socioeconomic level was computed. MAIN RESULTS: The city's estimated prevalence was 12.9 opioid addicts per 1000 inhabitants aged 15 to 44 years (95% CI: 10.1, 17.2), which represents 9176 persons. The highest rate was found in the inner city neighbourhood. Comparing rates obtained for each neighbourhood with their unemployment rates, a high correlation coefficient was obtained (r = 0.80, p < 0.001). CONCLUSION: The main contribution of this study is that of combining capture-recapture with the HPI to produce small area prevalence estimates, which would not have been possible using only one method. Areas with higher socioeconomic status showed proportionally low addiction prevalences, but in depressed areas, prevalences varied widely. (+info)
Rapid opioid detoxification during general anesthesia: a review of 20 patients.
(13/1183)
BACKGROUND: Opioid addiction therapy includes successful detoxification, rehabilitation, and sometimes methadone maintenance. However, the patient may have physical, mental, and emotional pain while trying to achieve abstinence. A new detoxification technique that incorporates general anesthesia uses a high-dose opioid antagonist to compress detoxification to within 6 h while avoiding the withdrawal. METHODS: After Institutional Review Board approval and detailed informed consent, 20 patients, American Society of Anesthesiologists status I-II, addicted to various opioids underwent anesthesia-assisted rapid opioid detoxification. After baseline hemodynamics and withdrawal scores were obtained, anesthesia was induced. After testing with 0.4 mg intravenous naloxone, 4 mg nalmefene, was infused over 2 to 3 h. After emergence, severity of withdrawal was scored before and after administration of 0.4 mg intravenous naloxone. After 24 h, patients began outpatient follow-up treatment while taking oral naltrexone. RESULTS: All 20 patients were successfully detoxified with no adverse anesthetic events. After the first post-treatment test dose of 0.4 mg naloxone, 13 of 20 patients had no signs of withdrawal and hemodynamic changes were minimal. Withdrawal scores were always very low and similar before and after detoxification. Three of 17 patients (18%) available for follow-up have remained abstinent from opioids since treatment (< or = 18 months). Four other patients are clean after brief relapses. CONCLUSIONS: Anesthesia-assisted opioid detoxification is an alternative to conventional detoxification. (+info)
Methadone treatment practices and outcome for opiate addicts treated in drug clinics and in general practice: results from the National Treatment Outcome Research Study.
(14/1183)
BACKGROUND: General practitioners (GPs) are increasingly urged to become more involved in the care and treatment of drug misusers. Little information is available about the effectiveness of treatments delivered in primary health care or specialist settings. The impact of treatment setting is investigated as part of the National Treatment Outcome Research Study (NTORS). This is the largest study of treatment outcome for drug misusers ever conducted in the United Kingdom (UK). AIM: This paper presents six-month treatment outcomes for patients who received community-based methadone treatment in either a specialist drug clinic or a general practice setting. METHOD: A prospective, multisite follow-up study of treatment outcome was conducted with 452 opiate addicts who had been given methadone treatment in primary health care and specialist clinic settings. Outcome data are presented for substance use behaviours, health, and crime. RESULTS: Improvements at follow-up were found among both the GP and the clinic-treated groups in drug-related problems, health, and social functioning. Problems at intake were broadly comparable among the clinic-based and the GP patients. Similar levels and types of improvement were found for both groups at six-month follow-up. CONCLUSIONS: Results demonstrate the feasibility of treating opiate addicts using methadone in primary health care settings, and show that treatment outcomes for such patients can be as satisfactory as for patients in specialist drug clinics. The GPs in our study are unrepresentative in their willingness to be actively involved with problem drug users; moreover, several services treated relatively large numbers of drug users. Issues surrounding the growth of 'GP specialists' are discussed. (+info)
Effects of opioid receptor agonists on cAMP second messenger system.
(15/1183)
AIM: To study the mechanism underlying the difference in physical dependence potential of morphine (Mor), methadone (Met), buprenorphine (Bup), etorphine (Eto), and dihydroetorphine (DHE). METHODS: Adenylate cyclase of NG108-15 cells were used for studying the effects of different opiates on cAMP second messenger system. RESULTS: Bup, DHE, and Eto were distinct from Mor in naloxone-precipitated rebound response of cAMP in NG108-15 cells chronically treated with these opiates. Naloxone given to NG108-15 cells treated with Mor for 24 h produced marked rebound response of adenylate cyclase. While no such rebound response was detected when the cells were treated with Bup, DHE, and Eto for 24 h. The naloxone-induced rebound response of cAMP in chronic Met-treated NG108-15 cells was also lower than that in chronic Mor-treated NG108-15 cells. Following a prolonged exposure to Bup, DHE, and Eto for 72 h, the naloxone-induced rebound response of cAMP in these cells was still markedly lower than that in Mor-treated cells. The substitution of Mor with Bup, Met, DHE, and Eto inhibited naloxone-induced rebound response of cAMP in chronic Mor-treated NG108-15 cells. CONCLUSION: There were distinct differences among these opiates in regulating cAMP second messenger system, which was related to their physical dependence potential. (+info)
Effects of low-pH treatment on cAMP second messenger system regulated by different opioid agonists.
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AIM: To study the mechanism of opioid agonists in regulation of cAMP second messenger system. METHODS: Low-pH treatment was used to deplete the stimulatory G protein (Gs) function. The effects of some opiates on adenylate cyclase were compared between control and low-pH treatment membranes. RESULTS: In contrast to dehydroetorphine (DHE), etorphine (Eto), morphine (Mor) and methadone (Met) substantially increased the inhibitory effects on adenylate cyclase in membranes prepared from naive and chronic Mor- or Met-treated NG108-15 cells by low-pH treatment. In contrast to Mor, DHE and Eto did not result in significant decrease in the inhibitory effects on adenylate cyclase in membranes from the cells treated chronically with DHE or Eto. Marked rebound of adenylate cyclase was also not observed in membranes from chronic DHE or Eto-treated cells when precipitated with naloxone. Low-pH treatment eliminated naloxone-induced rebound of adenylate cyclase in chronic Mor-treated cells. CONCLUSION: The difference in opiate-induced functional adaptive alteration of Gs is at least one biochemical mechanism of developing opiate tolerance and dependence. (+info)