Background: In many countries, the opioid agonists, buprenorphine and methadone, are licensed for maintenance treatment of opioid dependence. Many short-term studies have been performed, but little is known about long-term effects. Therefore, this study described over 6 years (1) mortality, retention and abstinence rates and (2) changes in concomitant drug use and somatic and mental health. Methods: A prevalence sample of n = 2,694 maintenance patients, recruited from a nationally representative sample of n = 223 substitution doctors, was evaluated in a 6-year prospectivelongitudinal naturalistic study. At 72 months, n = 1,624 patients were assessed for outcome; 1,147 had full outcome data, 346 primary outcome data and 131 had died; 660 individuals were lost to follow-up. Results: The 6-year retention rate was 76.6%; the average mortality rate was 1.1%. During follow-up, 9.4% of patients became “abstinent” and 1.9% were referred for drug-free addiction treatment. Concomitant drug use decreased and somatic health status and social parameters improved. Conclusions: The study provides further evidence for the efficacy and safety of maintenance treatment with opioid agonists. In the long term, the number of opioid-free patients is low and most patients are more or less continuously under opioid maintenance therapy. Further implications are discussed.

Background: In many countries, buprenorphine and methadone are licensed for the maintenance treatment (MT) of opioid dependence. Despite many short-term studies, little is known about the long-term (12-month) effects of these treatments in different settings, i.e. primary care-based (PMC) and specialized substitution centers (SSCs). Objectives: To describe over a period of 12 months: (1) mortality, retention and abstinence rates; (2) changes in concomitant drug use, somatic and mental health; and (3) to explore differences between different types of provider settings. Methods: 12-Month prospective-longitudinal naturalistic study with four waves of assessment in a prevalence sample of N= 2694 maintenance patients, recruited from a nationally representative sample of N= 223 substitution physicians. Results: The 12-month retention rate was 75%; the mortality rate 1.1%. 4.1% of patients became “abstinent” during follow-up. 7% were referred to drug-free addiction treatment. Concomitant drug use decreased and somatic health status improved. No significant improvements were observed for mental health and quality of life. When controlling for initial severity, small PMC settings revealed better retention, abstinence and concomitant drug use rates. Conclusion: The study underlines the overall 12-month effectiveness of various forms of agonist MT. Findings reveal relatively high retention rates, low mortality rates, and improvements in most 12-month outcome domains, except for mental health and quality of life. PMC settings appear to be a good additional option to improve access to MTs.

No description available.

<p>Metadon je sintetski agonist opijatnih receptora koji se primenjuje u sklopu supstitucione terapije opijatnih zavisnika metadonom (STM) i u terapiji hroničnog bola. Dugoročna primena STM je praćena blagim, uglavnom prolaznim, neželjenim delovanjima. Međutim, metadon pripada grupi lekova koji mogu da prouzrokuju prolongaciju korigovanog QT intervala (QTc) u elektrokardiogramu (EKG-u) i povećaju rizik za nastanak potencijalno fatalnih aritmija tipa torsades de pointes. Opijatni zavisnici metadon najče&scaron;će koriste u kombinaciji sa benzodiazepinima, i ova kombinacija lekova predstavlja faktor rizika za nastanak smrtnog ishoda. Iako je najveći broj lekara upoznat sa rizikom za razvoj respiratorne depresije prilikom primene opijata u kombinacji sa benzodiazepinima, velika studija otkriva da su ventrikularne aritmije i srčani zastoj najče&scaron;će prijavljivana neželjena delovanja metadona, primenjenog u kombinaciji sa benzodiazepinima. Ciljevi ovoga radu su da se analizom smrtnih slučajeva povezanih sa upotrebom metadona (MRDs) tokom desetogodi&scaron;njeg perioda na teritoriji Vojvodine i sprovođenjem kliničkog ispitivanja kod opijatnih zavisnika na STM proceni kardiolo&scaron;ka bezbednost primene metadona, posebno u kombinaciji sa benzodiazepinima. Sprovedena je retrospektivna studija za određivanje karakteristika MRDs na teritoriji Vojvodine, kao i kliničko ispitivanje u kome su učestvovali opijatni zavisnici koji počinju sa STM. Snimanje EKG-a (za izračunavanje QTc intervala) i uzorkovanje krvi (za određivanje koncentracije metadona i diazepama i vrednosti troponina) je sprovedeno kod svih učesnika istraživanja u 5 vremenskih tačaka (pre početka primene STM, 8. i 15. dana i nakon 1. i 6. meseca primene STM). Koncentracije metadona i diazepama u serumu su određivane metodom tečne hromatografije sa masenom spektrometrijom (LC-MS). U Vojvodini je zapažena rastuća tendencija MRDs, ali ni jedan od umrlih nije bio na STM, i najverovatnije su samoinicijativno koristili metadon i benzodiazepine. Patohistolo&scaron;ki nalaz na srcu može govoriti u prilog kardiotoksičnosti metadona i njegove kombinacije sa benzodiazepinima, pogotovo kod slučajeva sa pronađenim akutnim miokardijalnim o&scaron;tećenjem. &Scaron;to se tiče hroničnih promena na srcu, ne postoji mogućnosti da se potvrdi niti opovrgne uloga psihostimulanasa. Detektovane koncentracije metadona i diazepama kod MRDs su bile u opsegu terapijskih (&lt;1 &mu;g/ml). Poredeći socio-demografske karakteristike opijatnih zavisnika koji su počeli sa STM u ovom istraživanju sa podacima iz sličnih studija sprovedenih &scaron;irom sveta, zapažena je sličnost u pogledu velikog broja karakteristika. Srednje doze metadona 8., 15. dana i nakon 1. i 6. meseca primene STM su bile 40,23&plusmn;17,11 mg, 47,11&plusmn;16,79 mg, 50,00&plusmn;17,55 mg i 78,63&plusmn;18,14 mg, dok su srednje doze diazepama u istim vremenskim tačkama bile 35,92&plusmn;10,47 mg, 33,89&plusmn;9,23 mg, 28,33&plusmn;11,55 mg i 28,12&plusmn;11,67 mg. Srednje koncentracije metadona su u posmatranim tačkama ispitivanja iznosile 153,44&plusmn;111,51 ng/ml, 157,43&plusmn;112,39 ng/ml, 176,77&plusmn;118,56 ng/ml i 342,86&plusmn;181,54 ng/ml, dok su srednje koncentracije diazepama bile 923,00&plusmn;537,89 ng/ml, 923,76&plusmn;739,96 ng/ml, 560,74&plusmn;436,72 ng/ml i 1045,32&plusmn;932,72 ng/ml. Dužina QTc intervala pre primene STM je bila 411,87&plusmn;27,22 ms, tj. 414,64&plusmn;29,38 ms 8. dana STM, 416,97&plusmn;26,39 15. dana, i 425,20&plusmn;17,71 ms nakon 1. meseca tj. 423,50&plusmn;14,72 ms nakon 6. meseca primene STM. Pokazan je statistički značajan porast dužine QTc intervala nakon 1. i nakon 6. meseca primene STM u odnosu na vrednost pre primene STM, kako u grupi svih ispitanika, tako i u podgrupi mu&scaron;kog pola. Pokazano je postojanje statistički značajne korelacije između koncentracije metadona i dužine QTc intervala nakon 15. dana, 1. i 6. meseca primene STM, kako kod svih ispitanika, tako i u podgrupi mu&scaron;kog pola. Ova korelacija ostaje statistički značajna i ukoliko se uključe i drugi faktori &ndash; koncentracija diazepama i dužina perioda upotrebe heroina, kod svih ispitanika i u podgrupi mu&scaron;kog pola nakon 15 dana i mesec dana primene STM, kao i u podgrupi mu&scaron;kog pola nakon 6. meseca STM. Iako nijedan pacijent nije prijavio neko neželjeno delovanje metadona na nivou kardiovaskularnog sistema, najveći broj pacijenata oba pola se nakon prvog meseca primene STM žalio na pojačano znojenje i opstipaciju. Koncentracije metadona i diazepama u uzorcima krvi kod MRDs se nalaze u rasponu koncentracija ovih lekova u krvi ispitanika koji su učestvovali u prospektivnoj studiji. Trećina umrlih je imala samo znake akutnog o&scaron;tećenja srca, dok do porasta troponina i vrednosti QTc intervala preko 500 ms nije do&scaron;lo ni kod jednog ispitanika iz prospektivne studije. Potrebno je sprovesti dalja istraživanja sa ciljem razja&scaron;njenja moguće uloge benzodiazepina u povećanju kardiotoksičnosti metadona kod opijatnih zavisnika na STM.</p> / <p>Methadone is a synthetic agonist of opioid receptors which is used in methadone maintenance tratment (MMT) of opiate addicts as well as in the treatment of chronic pain. A long-term use of MMT is followed by mild, mostly transient, adverse effects. However, methadone belongs to a group of medicines which can provoke a prolongation of QTc (corrected QT) interval in electrocardiogram (ECG) and thus increase the risk from the development of potentially fatal arrhythmias &ndash; torsades de pointes. Moreover, methadone is widely associated with benzodiazepines use in heroin addicts, and this combination is considered as a risk factor for lethal outcome. Despite the fact that most of health care professionals are aware of possible respiratory depressant effect of methadone and benzodiazepines co-administration, recently published data reveal that ventricular arrhythmia and cardiac arrest are currently the most frequent adverse event attributed to methadone and benzodiazepine co-medication. The aim of this study is to assess cardiac safety of methadone use, especially in combination with benzodiazepines, by analyzing characteristics of methadone-related deaths (MRDs) during 10-year period as well as by conducting a clinical trial among opiate addicts in MMT. A retrospective study to determine the characteristics of MRDs in Vojvodina, as well as a clinical trial in which participated opiate addicts at the start of MMT were performed. ECG (to calculate QTc interval) and blood sampling (to determine methadone and diazepam concentrations and troponin values) were performed in all study participants at five time points (before the introduction of MMT, on 8th, on 15th day, after 1 and 6 months of MMT). Methadone and diazepam concentrations in serum were determined by using liquid chromatography-mass spectrometry (LC-MS). An increasing tendency of MRDs was observed in the region of Vojvodina, but none of the victims were under healthcare professionals&rsquo; control, and, most commonly, they used methadone and benzodiazepines, on their own initiative. Pathohistological findings in the heart in MRDs might support cardiac adverse effects of methadone and its combination with benzodiazepines, especially in cases with acute myocardial damage. As for the chronic heart changes, we can neither confirm nor exclude the role of psychostimulants. Detected concentrations of methadone and diazepam were in therapeutic range (&lt;1 &mu;g/ml). Comparing socio-demographic characteristics of opiate addicts who started with MMT in this study with data from similar studies conducted worldwide, the similarity in terms of large number of features was observed. The mean methadone dose on the 8th, 15th days, and after 1 and 6 months of MMT was 40.23&plusmn;17.11 mg, 47.11&plusmn;16.79 mg, 50.00&plusmn;17.55 mg and 78.63&plusmn;18.14 mg, respectively, while the mean diazepam dose at the same time points was 35.92&plusmn;10.47 mg, 33.89&plusmn;9.23 mg, 28.33&plusmn;11.55 mg and 28.12&plusmn;11.67 mg, respectively. The mean methadone concentration at observed time points was 153.44&plusmn;111.51 ng/ml, 157.43&plusmn;112.39 ng/ml, 176.77&plusmn;118.56 ng/ml and 342.86&plusmn;181.54 ng/ml, respectively, while the mean diazepam concentration was 923.00&plusmn;537.89 ng/ml, 923.76&plusmn;739.96 ng/ml, 560.74&plusmn;436.72 ng/ml and 1045.32&plusmn;932.72 ng/ml, respectively. The length of QTc interval before the introduction of MMT was 411.87&plusmn;27.22 ms, 414.64&plusmn;29.38 ms on the 8th day of MMT, 416.97&plusmn;26.39 on the 15th day of MMT, after 1 month of MMT 425.20&plusmn;17.71 ms and after 6 months of MMT 423.50&plusmn;14.72 ms. There was a statistically significant increase in the length of QTc interval after 1 and 6 months of MMT in comparison to the value before the application of MMT, within the whole group of patients and in the subgroup of men. A statistically significant correlation between the concentration of methadone and QTc interval length after 15 days, 1 and 6 months of MMT, both in the whole group and in the subroup of men was observed. The correlation remained statistically significant if the other factors, such as concentration of diazepam and the length of heroin use, were included, in all patients and in the subgroup of men after 15 days and one month of MMT as well as in the subgroup of men after 6 months of MMT. Although none of the patients reported any cardiac adverse effect of methadone, the majority of them complained of sweating and constipation after the first month of MMT. Concentrations of methadone and diazepam in blood samples in MRDs were within the range of concentrations of these drugs in blood of patients who participated in the prospective study. In one third of MRDs only signs of acute myocardial damage were detected, while an increase in troponin values and the length of QTc interval over 500 ms did not occur in any patient in the prospective study. Further studies could clarify the possible role of benzodiazepines in the increasing cardiotoxicity of methadone in opiate addicts in MMT.</p>

The thesis is devoted to the issue of addiction services with a focus on substitution treatment. Theoretical part focuses on presenting of susbstitution treatment, its history and description of the substitution substances and their effects on the human body. Describes the abuse of substitution treatment by problem drug users and tries to map out the various addiction treatment services with a focus on substitution treatment in Prague. The research section defines the attitude of society towards the establishment and functioning of Prague substitution centers. The thesis concludes with an overview of addiction services and substitution programs in the capital city of Prague. Powered by TCPDF (www.tcpdf.org)

<p>Uvod: Temperament predstavlja skup psiholo&scaron;kih osobina, to jest način, brzinu i jačinu umnog i emotivnog reagovanja svojstven pojedincu, odnosno njegovu narav, ćud, prirodu. Savremena istraživanja premorbidnog afektivnog tipa temperamenta, govore u prilog njegovog značaja u etiologiji i kliničkoj evaluaciji bolesti zavisnosti. Cilj: Utvrditi i uporediti temperament kod osoba obolelih od mentalnog poremećaja i poremećaja pona&scaron;anja zbog upotrebe opijata i zdrave populacije. Materijal i metode: Istraživanje je urađeno po tipu studije preseka, i obuhvatalo je 200 ispitanika, podeljenih u dve grupe. Ispitivanu grupu činilo je 100 stabilnih zavisnika od opijata na supstitucionoj terapiji metadonom, starosti od 18 do 40 godina, bez komorbidne bolesti iz kruga psihotičnih poremećaja. U kontrolnu grupu uvr&scaron;teno je 100 zdravih osoba &scaron;to sličnijih sociodemografskih karakteristika sa ispitivanom grupom. Njihov temperament je određivan TEMPS-A upitnikom samoprocene. Rezultati: Utvrđeno je statistički značajno če&scaron;će postojanje dominantog temperamenta kod zavisnika, kao i prisustvo depresivnog, ciklotimnog, razdražljivog i anksioznog temperamenta, koji govore u prilog osnovne razlike između zdrave populacije i populacije sa mentalnim poremećajem i poremećajem pona&scaron;anja zbog upotrebe opijata. Zaključak: Afektivni temperament, kao premorbidna karakteristika ličnosti, ima uticaja na nastanak i razvoj zavisnosti od opijata. Stoga je od značaja da se uzmu u obzir osobine hipertimnog temperamenta kao protektivnog ili depresivnog, ciklotimnog, radražljivog i anksioznog temperamenta kao rizičnih faktora u etiologiji, prevenciji i terapiji bolesti zavisnosti.</p> / <p>Introduction: Temperament is a set of psychological characteristics, ie the speed and strength of mind and emotional reactions peculiar to the individual, or his character, temperament, nature. Modern research of the premorbid affective temperament is in favor of its significance in the etiology and clinical evaluation of substance abuse. The Aim: To determine and compare the temperament of people suffering from mental and behavioral disorders due to use of opioids and healthy population. Materials and Methods: The study was cross-sectional, and 200 subjects were included and divided into two groups. The study group included stable opiate addicts on substitution therapy with methadone, aged 18 to 40 years, without co-morbid psychotic disorders. The Control group consisted of 100 healthy individuals with similar sociodemographic data as the Study group. Their temperament was determined with the TEMPS-A auto-questionnaire. Results: Statistical significance of a dominant temperament was more frequently found in the subjects with opioid dependence, as well as in depressive, cyclothymic, anxious and irritable temperament, which leads to the fundamental differences between a healthy population and a population with mental and behavioral disorders due to the use of opioids. Conclusion: Affective temperament, as a premorbid personality trait, has an impact on the occurence and development of opiate dependence. Therefore, it is essential to take into account the characteristics of a hyperthymic temperament as a protective factor or depressive, cyclothymic, irritable and anxious temperament as risk factors in etiology, prevention and treatment of addiction.</p>

In this project a LC-MS-method for the analysis of gamma-hydroxybutyrate, gamma-butyrolactone, 1,4-butanediol, amphetamine and methadone was developed. Initially, the efficiency of the ionisation of the analytes was evaluated with respect to the ionisation technique (ESI, APCI and APPI) and the composition of the mobile phase. In the next step a number of different columns was tested in order to find the one with the greatest potential for separation of the substances in question. Using the selected column, the separation was optimised by means of experimental design and the software The Unscrambler 7.8. The parameters studied were the flow rate, the column temperature and the mobile phase composition. The response variables were the resolution between the target compounds and the retention time of the last eluting compound. These experiments showed that, in order to obtain the best ionisation, the mobile phase should consist of 5 mM formic acid in water and acetonitrile. ESI should be used in the positive mode for all analytes except gamma-hydroxybutyrate, for which the negative mode should be applied. The Hypercarb column exhibited superior retention of the analytes and was therefore selected for further optimisation. The dimensions of this column were 2.1 x 50 mm and the particle size 5 μm, connected to a 2.1 x 10 mm precolumn containing the same packing material. The optimum of the flow rate and the column temperature were 250 μl/min and 20 ºC respectively. For the separation of gamma-hydroxybutyrate, gamma-butyrolactone and 1,4-butanediol the mobile phase consisted of 100% water with 5 mM formic acid. Thereafter a gradient, up to 70% acetonitrile with 5 mM formic acid, was used in order to elute amphetamine and methadone. Efforts were also made to find an internal standard for the method. However, none of the compounds tested was found suitable. In order to get the method usable for routine analysis, which is the goal, further work is required. A suitable internal standard needs to be added to the method and thereafter work remains with validation of the method.

毒品濫用問題乃世界各國共通之施政難題，我國政府於1993年宣布向毒品宣戰，並在2005年8月引進美沙酮替代療法（Methadone Maintenance Treatment，MMT），於全國各縣市推動毒品減害計畫。但歷經十餘年之努力，毒品人口與整體毒品再犯率截至2010年底並未明顯降低，足見毒品防制政策有全面檢視問題癥結，重新調整執行策略之必要。本研究就此現象探討三項議題：1.毒品防制領域，IT有無著力之空間？ 2.以美沙酮替代療法為主之毒品防制策略在台灣地區推行是否發揮預期的效果？現行做法有無改善空間？ 3.出監毒癮者復歸社會後再犯率高，其最需要政府的幫助為何，方能有效降低再犯毒品罪之誘因？。三項議題互為關聯。 本研究探訪毒品防制第一線工作人員，並參考國內外毒品減害文獻，歸納目前毒品危害防制工作推動上的困境，探究IT可出力之空間，並提出“毒品成癮者資訊總歸戶”的概念。整合法務、警政、衛生醫療等毒品防制資訊，建立跨部會即時歸戶資料庫並建立部會間協同作業之標準作業程序（SOP），以提升毒品防制工作之效率。進而運用歸戶系統之客觀數據，評量毒品替代療法政策之推行成效，並實際訪問領域專家及調查毒品犯社會適應之困難與需求，以歸納具體、可行之解決方案。 研究發現資訊系統可改善毒品危害防制中心效率，但不能單獨讓毒品防制工作之網絡有效運轉，現行毒品防制組織、制度問題之發現與解決更是關鍵。本文並依客觀數據之分析及實地訪問、調查結果，提出多項制度變革之建議，以供政府權責機關參採。 / Background:Drug abuse problems have been a global concern issue. Taiwan’s government introduced Methadone Maintenance Treatment (MMT) in Aug. 2005, now it has become one of the major strategies in fighting drug abuse. Whereas, up to 2010 MMT strategy still not shows effectiveness in reduce drug population and recidivism. The aim of this study is to: Provide the value to the Drug Abuse Provention System in R.O.C.through IT approach,and to evaluate whether MMT is performed adequately in Taiwan.If not,what are the key factors? The study will provide objective evidence and suggestions to authorities for better decision making. Methods: This study used Prove of Concept (POC) and experiment approachs. Build software system and SOP to prove the concept of “National Drug Addicts Supporting and Monitoring System (NDASMS)” can enhance the efficiency of Information Intergration among government agencies of drug prevention effectively. The study also used the data of NDASMS to evaluate the efficacy of MMT implementation in Taiwan, and find the reasons why MMT dose not work as expected. Result: The IT approach have been proved that enhance the infromation integration effectively among agencies, but IT can,t make the Chain of National Drug Provention Mechanism improve alone.The adequacy of MMT implementation and its supporting measures in Taiwan need to be further examined.

<p>In this project a LC-MS-method for the analysis of gamma-hydroxybutyrate, gamma-butyrolactone, 1,4-butanediol, amphetamine and methadone was developed.</p><p>Initially, the efficiency of the ionisation of the analytes was evaluated with respect to the ionisation technique (ESI, APCI and APPI) and the composition of the mobile phase. In the next step a number of different columns was tested in order to find the one with the greatest potential for separation of the substances in question. Using the selected column, the separation was optimised by means of experimental design and the software The Unscrambler 7.8. The parameters studied were the flow rate, the column temperature and the mobile phase composition. The response variables were the resolution between the target compounds and the retention time of the last eluting compound.</p><p>These experiments showed that, in order to obtain the best ionisation, the mobile phase should consist of 5 mM formic acid in water and acetonitrile. ESI should be used in the positive mode for all analytes except gamma-hydroxybutyrate, for which the negative mode should be applied. The Hypercarb column exhibited superior retention of the analytes and was therefore selected for further optimisation. The dimensions of this column were 2.1 x 50 mm and the particle size 5 μm, connected to a 2.1 x 10 mm precolumn containing the same packing material. The optimum of the flow rate and the column temperature were 250 μl/min and 20 ºC respectively. For the separation of gamma-hydroxybutyrate, gamma-butyrolactone and 1,4-butanediol the mobile phase consisted of 100% water with 5 mM formic acid. Thereafter a gradient, up to 70% acetonitrile with 5 mM formic acid, was used in order to elute amphetamine and methadone. Efforts were also made to find an internal standard for the method. However, none of the compounds tested was found suitable.</p><p>In order to get the method usable for routine analysis, which is the goal, further work is required. A suitable internal standard needs to be added to the method and thereafter work remains with validation of the method.</p>

本研究的主要目的在於探討美沙冬的使用者是否具有抑制控制能力缺損、對海洛因相關刺激是否具有注意力偏誤，以及是否有彈性認知轉換能力上的問題。 研究使用的是Noel等人（2005,2007）發展出來的Go/No-Go作業，並使用海洛因圖片與中性圖片為作業刺激，分別測量受試者在作業中的反應正確率、反應遺漏數、反應犯錯數、平均反應時間、決定偏誤與區辨度，並且使用依賴嚴重度量表，以了解受試者對海洛因的依賴嚴重度與Go/No-Go作業各指標之間的相關。 　　美沙冬組樣本選取自八里療養院土城門診部之接受美沙冬治療者，共17人，經由網路招募之健康控制組十九人，受試者一共三十六人。共變數分析之結果顯示在Go/No-Go作業的正確率、遺漏數、區辨度和決定偏誤等指標上，發現組別與情境轉換之交互作用，顯示使用美沙冬之受試者具有彈性認知能力上的缺損，因此在有轉換的區段之中，無法快速地適應新的作答規則。此外，Go/No-Go作業結果未發現美沙冬使用者之抑制缺損與對海洛因相關圖片之注意力偏誤之現象。 　　依賴嚴重度與Go/No-Go作業的指標相關研究則發現，其依賴嚴重度越高，其在非轉換情境中對海洛圖片的犯錯數越低、決定偏誤越高，顯示美沙冬使用者似乎在沒有情境轉換的區段中，會將其注意力資源分配在海洛因圖片上，忽略非海洛因圖片，顯示其注意力較具選擇性。 / The goal of this study is to explore the inhibitory deficits、attentional bias towards heroin-related cues and cognition flexibility of current methadone users. The Go/No-go task used here was previously developed by Noel et al. (2005, 2007). Heroin-related pictures and neural pictures were presented as targets or non-targets. Accuracy rate、omission、commission、average reaction time、decision bias(C) and discrimination (d’) were being measured individually. The relation between the severity of heroin dependence and task performance was also investigated. The 17 subjects in methadone group were currently methadone maintenance treatment patients from Bali psychiatric center, and the 19 control group subjects without a drug using history were recruited by internet advertisement. The covariance analysis revealed interactions of group and shift/non-shift condition on accuracy rate、omission、decision bias(C) and discrimination (d’), indicating a cognitive flexibility deficits in methadone users. They had difficulty adapting to new rules in shifting conditions. No inhibitory deficits or attentional bias were found so far in this study. The relation between heroin dependence and Go/No-go task performance revealed that the more dependent the methadone subjects were, the less commission errors they made, the higher decision bias score they got towards heroin pictures in non-shifting conditions. It seemed that the methadone users were prone to allocate more attention resource to heroin-related pictures in non-shifting conditions, suggesting a more selective attention process.