A non-hallucinogenic psychedelic analogue with therapeutic potential.

The psychedelic alkaloid ibogaine has anti-addictive properties in both humans and animals1. Unlike most medications for the treatment of substance use disorders, anecdotal reports suggest that ibogaine has the potential to treat addiction to various substances, including opiates, alcohol and psychostimulants. The effects of ibogaine-like those of other psychedelic compounds-are long-lasting2, which has been attributed to its ability to modify addiction-related neural circuitry through the activation of neurotrophic factor signalling3,4. However, several safety concerns have hindered the clinical development of ibogaine, including its toxicity, hallucinogenic potential and tendency to induce cardiac arrhythmias. Here we apply the principles of function-oriented synthesis to identify the key structural elements of the potential therapeutic pharmacophore of ibogaine, and we use this information to engineer tabernanthalog-a water-soluble, non-hallucinogenic, non-toxic analogue of ibogaine that can be prepared in a single step. In rodents, tabernanthalog was found to promote structural neural plasticity, reduce alcohol- and heroin-seeking behaviour, and produce antidepressant-like effects. This work demonstrates that, through careful chemical design, it is possible to modify a psychedelic compound to produce a safer, non-hallucinogenic variant that has therapeutic potential.

A novel tramadol-polycaprolactone implant could palliate heroin conditioned place preference and withdrawal in rats: behavioral and neurochemical study.

Drug dependence is a chronic brain disease characterized by craving and recurrent episodes of relapse. Tramadol HCl is a promising agent for withdrawal symptoms management, considering its relatively low abuse potential and safety. Oral administration, however, is not preferred in abstinence maintenance programs. Introducing an implantable, long-lasting formula is suggested to help outpatient abstinence programs achieve higher rates of treatment continuation. Tramadol implants (T350 and T650) were prepared on polycaprolactone polymer ribbons by the wet method. Male Wistar rats were adapted to heroin-conditioned place preference (CPP) at escalating doses (3-30 mg/kg, intraperitoneally, for 14 days). Implants were surgically implanted in the back skin of rats. After 14 days, the CPP score was recorded. Naloxone (1 mg/kg, intraperitoneally) was used to induce withdrawal on day 15, and symptoms were scored. Elevated plus maze and open field tests were performed for anxiety-related symptoms. Striata were analyzed for neurochemical changes reflected in dopamine, 3,4-dihydroxyphenyl acetic acid, gamma-aminobutyric acid, and serotonin levels. Brain oxidative changes including glutathione and lipid peroxides were assessed. The tramadol implants (T350 and T650) reduced heroin CPP and limited naloxone-induced withdrawal symptoms. The striata showed increased levels of 3,4-dihydroxyphenyl acetic acid, and serotonin and decreased levels of gamma-aminobutyric acid and dopamine after heroin withdrawal induction, which were reversed after implanting T350 and T650. Implants restore the brain oxidative state. Nonsignificant low naloxone-induced withdrawal score after the implant was used in naive subjects indicating low abuse potential of the implants. The presented tramadol implants were effective at diminishing heroin CPP and withdrawal in rats, suggesting further investigations for application in the management of opioid withdrawal.

DRD2 TaqIA polymorphism-related functional connectivity between anterior insula and dorsolateral prefrontal cortex predicts the retention time in heroin-dependent individuals under methadone maintenance treatment.

BACKGROUND: Dopamine receptor D2 (DRD2) TaqIA polymorphism has an influence on addiction treatment response and prognosis by mediating brain dopaminergic system efficacy. Insula is crucial for conscious urges to take drugs and maintain drug use. However, it remains unclear about the contribution of DRD2 TaqIA polymorphism to the regulation of insular on addiction behavioral and its relation with the therapeutic effect of methadone maintenance treatment (MMT). METHODS: 57 male former heroin dependents receiving stable MMT and 49 matched male healthy controls (HC) were enrolled. Salivary genotyping for DRD2 TaqA1 and A2 alleles, brain resting-state functional MRI scan and a 24-month follow-up for collecting illegal-drug-use information was conducted and followed by clustering of functional connectivity (FC) patterns of HC insula, insula subregion parcellation of MMT patients, comparing the whole brain FC maps between the A1 carriers and non-carriers and analyzing the correlation between the genotype-related FC of insula sub-regions with the retention time in MMT patients by Cox regression. RESULTS: Two insula subregions were identified: the anterior insula (AI) and the posterior insula (PI) subregion. The A1 carriers had a reduced FC between the left AI and the right dorsolateral prefrontal cortex (dlPFC) relative to no carriers. And this reduced FC was a poor prognostic factor for the retention time in MMT patients. CONCLUSION: DRD2 TaqIA polymorphism affects the retention time in heroin-dependent individuals under MMT by mediating the functional connectivity strength between left AI and right dlPFC, and the two brain regions are promising therapeutic targets for individualized treatment.

Metabolic and functional substrates of impulsive decision-making in individuals with heroin addiction after prolonged methadone maintenance treatment.

Elevated impulsivity has been frequently reported in individuals with opioid addiction receiving methadone maintenance therapy (MMT), but the underlying neural mechanisms and cognitive subprocesses are not fully understood. We acquired functional magnetic resonance imaging (fMRI) data from 37 subjects with heroin addiction receiving long-term MMT and 33 healthy controls who performed a probabilistic reversal learning task, and measured their resting-state brain glucose using fluorine-18-fluorodeoxyglucose positron emission tomography (18F-FDG PET). Subjects receiving MMT exhibited significantly elevated self-reported impulsivity, and computational modeling revealed a marked impulsive decision bias manifested as switching more frequently without available evidence. Moreover, this impulsive decision bias was associated with the dose and duration of methadone use, irrelevant to the duration of heroin use. During the task, the switch-related hypoactivation in the left rostral middle frontal gyrus was correlated with the impulsive decision bias while the function of reward sensitivity was intact in subjects receiving MMT. Using prior brain-wide receptor density data, we found that the highest variance of regional metabolic abnormalities was explained by the spatial distribution of µ-opioid receptors among 10 types of neurotransmitter receptors. Heightened impulsivity in individuals receiving prolonged MMT is manifested as atypical choice bias and noise in decision-making processes, which is further driven by deficits in top-down cognitive control, other than reward sensitivity. Our findings uncover multifaceted mechanisms underlying elevated impulsivity in subjects receiving MMT, which might provide insights for developing complementary therapies to improve retention during MMT.

Cognitive Enhancer Donepezil Attenuates Heroin-Seeking Behavior Induced by Cues in Rats.

PURPOSE: Opioid use disorder is a significant global problem. Chronic heroin use is associated with impairment of cognitive function and conscious control ability. The cholinergic system can be disrupted following heroin administration, indicating that activation of the cholinergic system may prevent chronic heroin misuse. Donepezil as an inhibitor of cholinesterase has been reported to clinically improve cognition and attention. In this study, the inhibition of heroin self-administration and heroin-seeking behaviours by donepezil were evaluated in rats. METHODS: Rats were trained to self-administer heroin every four hours for 14 consecutive days under a fixed ratio 1 (FR1) reinforcement schedule, then underwent withdrawal for two weeks. A progressive ratio schedule was then used to evaluate the relative motivational value of heroin reinforcement. After withdrawal, a conditioned cue was introduced for the reinstatement of heroin-seeking behaviour. Donepezil (0.3-3 mg/kg, i.p.) was used during both the FR1 heroin self-administration and progressive ratio schedules. Immunohistochemistry was used to investigate the mechanism of action of donepezil in the rat brain. RESULTS: Pre-treatment with high dose donepezil (3 mg/kg) but not low doses (0.3-1 mg/kg) significantly inhibited heroin self-administration under the FR1 schedule. Donepezil decreased motivation values under the progressive ratio schedule in a dose-dependent manner. All doses of donepezil (1-3 mg/kg) decreased the reinstatement of heroin seeking induced by cues. Correlation analysis indicated that the inhibition of donepezil on heroin-seeking behaviour was positively correlated with an increased expression of dopamine receptor 1 (D1R) and dopamine receptor 2 (D2R) in the nucleus accumbens (NAc) and increased expression of choline acetyltransferase (ChAT) in the ventral tegmental area (VTA). CONCLUSIONS: The present study demonstrated that donepezil could inhibit heroin intake and heroin-seeking behaviour. Further, donepezil could regulate dopamine receptors in the NAc via an increase of acetylcholine. These results suggested that donepezil could be developed as a potential approach for the treatment of heroin misuse.

A method of diamorphine (heroin) administration for harm reduction.

As societal attitudes toward narcotics have changed, harm reduction strategies have emerged which make it safer to inject intravenous drugs. Diamorphine (heroin) is commonly sold as its free base-better known as brown-which has extremely poor aqueous solubility. As such, it needs to be chemically modified (cooked) to enable administration. Needle exchange programmes commonly supply citric or ascorbic acids which facilitate intravenous administration by increasing heroin solubility. If heroin users mistakenly add too much acid, the low solution pH can cause damage to their veins and, after repeated injury, could result in the loss of that injection site. Currently, advice cards supplied with these exchange kits suggest that the acid should be measured in pinches, which could result in considerable error. This work employs Henderson-Hasselbalch models to analyse the risk of venous damage by placing solution pH within the context of the buffer capacity of the blood. These models also highlight the significant risk of heroin supersaturation and precipitation within the vein, an event that has the potential to cause further harm to the user. This perspective closes with a modified administration method which could be included as part of a wider harm reduction package.

Safety and feasibility of intranasal heroin-assisted treatment: 4-week preliminary findings from a Swiss multicentre observational study.

BACKGROUND: Heroin-assisted treatment (HAT) is effective for individuals with severe opioid use disorder (OUD) who do not respond sufficiently to other opioid agonist treatments. It is mostly offered with injectable diacetylmorphine (DAM) or DAM tablets creating a barrier for individuals who need the rapid onset of action but are either unable or unwilling to inject, or primarily snort opioids. To explore another route of administration, we evaluated the safety and feasibility of intranasal (IN) DAM. METHODS: This is a multicentre observational cohort study among patients in Swiss HAT. All patients planning to receive IN DAM within the treatment centres were eligible to participate. Participants were either completely switched to IN DAM or received IN DAM in addition to other DAM formulations or opioid agonists. Patients were followed up for four weeks. Sociodemographic characteristics, current HAT regimen, reasons for starting IN DAM, IN DAM doses, number of injection events in the sample, IN DAM continuation rate, and appearance of adverse events and nose-related problems were evaluated. RESULTS: Participants (n = 52) reported vein damage, preference for nasal route of administration, and desire of a stronger effect or for a less harmful route of administration as primary reasons for switching to IN DAM. After four weeks, 90.4% of participants (n = 47) still received IN DAM. Weekly average realised injection events decreased by 44.4% from the month before IN DAM initiation to the month following. No severe adverse events were reported. CONCLUSIONS: After four weeks, IN DAM was a feasible and safe alternative to other routes of administration for patients with severe OUD in HAT. It addressed the needs of individuals with OUD and reduced injection behaviour. More long-term research efforts are needed to systematically assess efficacy of and patient satisfaction with IN DAM.

A 35-year follow-up study of patients admitted to methadone treatment between 1982-1984 in Asturias, Spain. / Estudio de seguimiento de 35 años de pacientes admitidos a tratamiento con metadona entre 1982-1984 en Asturias, España.

The objective was to evaluate outcomes in a heroin-dependent population 35 years after first enrolment in methadone maintenance treatment (MMT).  An ad hoc protocol was used to assess drug misuse, treatment, and drug-related morbidity in the survivor sample. The standardized mortality ratio (SMR) and 95% confidence interval (CI) were calculated.  A total of 214 heroin-dependent patients entered MMT between 1982 and 1984 in the Asturias Public Health Service. Information was received on 195 subjects, of whom 146 were deceased.  Men accounted for 77.5% of the study cohort. Over the 35-year follow-up period, the SMR was 11.75 (95% CI = 9.95 - 13.77). In the survivor sample, 5.7% were still enrolled in MMT; human immunodeficiency virus (HIV) was diagnosed in 38.77% and hepatitis B/C in 73.46%. No differences were found between sexes in mortality or HIV and hepatitis B/C status. None of the female survivors were using heroin at the 35-year follow-up compared with 5.26% of males. In conclusion, our study confirms the high long-term mortality rate of heroin addicts, even after enrollment in MMT.

El objetivo fue evaluar el estado de una población dependiente a la heroína 35 años después de su primera inscripción en un tratamiento de mantenimiento con metadona (TMM). Se utilizó un protocolo ad hoc para evaluar morbilidad, consumo y tratamiento de la adicción en la muestra de supervivientes. Se calculó la razón de mortalidad estandarizada (RME) con un intervalo de confianza (IC) del 95%. Un total de 214 pacientes ingresaron en TMM entre 1982 y 1984 en el Servicio de Salud Pública de Asturias. Se recibió información sobre 195 sujetos, de los cuales 146 habían fallecido. Los hombres representaron el 77,5% de la cohorte del estudio. Durante el período de seguimiento de 35 años, la RME fue de 11,75 (IC 95% = 9,95 ­ 13,77). En la muestra de supervivientes, el 5,7% todavía estaba inscrito en TMM; el virus de inmunodeficiencia humana (VIH) se diagnosticó en un 38,77% y la hepatitis B/C en un 73,46%; el consumo actual de heroína se informó en un 4,1%. No hubo diferencias de género en la mortalidad o la condición de VIH y hepatitis B/C. Ninguna de las mujeres consumía heroína en el seguimiento de 35 años en comparación con el 5,26% de los hombres. En conclusión, nuestro estudio confirma la alta tasa de mortalidad a largo plazo, incluso después de la inscripción en TMM.

Pharmacogenetic study of methadone treatment for heroin addiction: associations between drug-metabolizing gene polymorphisms and treatment efficacy.

OBJECTIVES: Opioid dependence is currently one of the most serious problems affecting the social norms and public health system. Methadone maintenance therapy (MMT) is being widely used in treating heroin-dependent patients. The mechanism of methadone metabolism and disposition has been shown to involve cytochrome P450 (CYP450) and P-glycoprotein. The aim of this study was to explore the relationships among genetic polymorphisms, BMI and effective dose of methadone used in MMT within a northern Taiwan cohort. METHODS: One hundred heroin-dependent patients were enrolled in the study. The clinical data gathered included methadone dose, sex and BMI. DNA was collected from the oral swab of the participants to analyze the relevant alleles. RESULTS: An effective methadone dose correlated with sex, BMI and the presence of ABCB1 2677GG (rs2032582) and CYP2B6 516GG (rs374527). Furthermore, the CYP2B6 516GG homozygote was related to a higher average dose of methadone (GG: 68.50 ± 32.43; GT: 52.28 ± 25.75; TT: 44.44 ± 29.64; P < 0.02), whereas the ABCB1 2677GG homozygote was related to a lower dose (GG: 51.09 ± 20.83; GT: 69.65 ± 37.51; TT: 62.52 ± 30.44; P < 0.05). We examined the predictive effect of polymorphisms combined with sex and BMI on methadone dose by conducting multiple linear regressions. Our data predicted the average dose of methadone in approximately 30% of heroin-dependent patients. CONCLUSION: The interactions between genetic polymorphisms and clinical features proved useful in identifying the effective dose of MMT for heroin-dependent patients in Taiwan more precisely.

Glucagon-like peptide-1 receptor agonist, liraglutide, reduces heroin self-administration and drug-induced reinstatement of heroin-seeking behaviour in rats.

Drug addiction is a chronic brain disease characterized by the uncontrolled use of a substance. Due to its relapsing nature, addiction is difficult to treat, as individuals can relapse following even long periods of abstinence and, it is during this time, that they are most vulnerable to overdose. In America, opioid overdose has been increasing for decades, making finding new treatments to help patients remain abstinent and prevent overdose deaths imperative. Recently, glucagon-like peptide-1 (GLP-1) receptor agonists have shown promise in reducing motivated behaviours for drugs of abuse. In this study, we test the effectiveness of the GLP-1 analogue, liraglutide (LIR), in reducing heroin addiction-like behaviour, and the potential side effects associated with the treatment. We show that daily treatment with LIR (0.1 mg/kg sc) increases the latency to take heroin, reduces heroin self-administration, prevents escalation of heroin self-administration and reduces drug-induced reinstatement of heroin-seeking behaviour in rats. A 1-h pretreatment time, however, was too short to reduce cue-induced seeking in our study. Moreover, we showed that, while LIR (0.1, 0.3, 0.6 and 1.0 mg/kg sc) supported conditioned taste avoidance of a LIR-paired saccharin cue, it did not elicit intake of the antiemetic kaolin in heroin-naïve or heroin-experienced rats. Further, 0.1 mg/kg LIR did not produce great disruptions in food intake or body weight. Overall, the data show that LIR is effective in reducing heroin taking and heroin seeking at doses that do not cause malaise and have a modest effect on food intake and body weight gain.

Structural violence and the need for compassionate use of methadone in Mexico.

BACKGROUND: Epidemiological data from Mexico have documented an increase in heroin use in the last decade. However, there is no comprehensive care strategy for heroin users, especially those who have been accused of a crime. The objective of this study was to describe the heroin and methadone use of intravenous heroin users of both sexes who have been in jail, to offer evidence for the formulation of health policy. METHODS: This study used an ethnographic approach, with open-ended interviews carried out from 2014 to the present. Heroin users of both sexes attending a private methadone clinic in Mexico City were invited to participate. The sample was non-probabilistic. All interviews were audiotaped and transcribed, and narratives were analyzed using thematic analysis. RESULTS: Participants in this study were 33 users of heroin, two of them women, who had been in prison. They ranged in age from 33 to 62 years, had used heroin for a period of 13-30 years, and were from three states: Michoacan, Oaxaca, and Mexico City. Three principal categories of analysis were structured: 1. Pilgrimage for help (dynamics of the drama of suffering, pain, and time through health care spaces); 2) methadone use as self-care; and 3) accessibility to methadone treatment. The impossibility of access to methadone treatment is a condition which motivates users in their journey. The dynamics of methadone use are interpreted as a form of self-care and care to avoid substance use. Reducing the psychological, physical, and harmful effects of the substance allows them to perform daily activities. The inability to access treatment leads to a significant effect on users who experience structural violence. CONCLUSION: Compassionate methadone treatment and holistic attention should be considered as a way to meet patients' needs and mitigate their suffering, based on public health policy that allows for human rights-based care.

Association between rs1799971 in the mu opioid receptor gene and methadone maintenance treatment response.

OBJECTIVE: Genetic variations can affect individual response to methadone maintenance treatment (MMT) for heroin addiction. The A118G variant (rs1799971) in the mu opioid receptor gene (OPRM1) is a potential candidate single nucleotide polymorphism (SNP) for personalized MMT. This study determined whether rs1799971 is related to MMT response or dose. METHODS: We recruited 286 MMT patients from a Han Chinese population. The rs1799971 genotype was determined via TaqMan genotyping assay. The genetic effect of this SNP on MMT response or dose was evaluated using logistic regression. A meta-analysis was performed to merge all available data to evaluate the role of rs1799971 in MMT using RevMan 5.3 software. RESULTS: No statistical significance was observed in the association between the OPRM1 rs1799971 and MMT response or dose in our Chinese cohort. Meta-analysis indicated that the OPRM1 A118G variation was not significantly associated with MMT response or dose requirement. CONCLUSION: The results suggest that rs1799971 in OPRM1 might not play a critical role alone in influencing MMT response or dose.

Different outcomes of methadone maintenance therapy in rehabilitated and relapsed drug addicts: significance of liver and renal biomarkers.

Methadone eliminates heroin use, reduces death rates and criminality associated with heroin use, and improves patients' health and social productivity. This study included long-term addicts who completed a methadone therapy program as well as relapsed patients. Liver and renal markers important for methadone metabolism were analyzed. Renal markers included urea and creatinine, while hepatic markers included total bilirubin, AST, ALT, γGT, and LDH as nonspecific but significant parameters of liver metabolism. The study included 34 male and 6 female heroin-dependent patients undergoing a rehabilitation program with methadone maintenance treatment (MMT). During therapy, average values ​​of all parameters remained within the reference interval but individual parameters in some patients were very high. Significant differences for urea (0.00) and very high individual variations in all parameters, especially γGT and LDH, were found in patients who were in relapse. Age of the patients did not show a correlation with the presence of significant differences in serum biochemical parameters during therapy. Prolonged use of methadone therapy stabilizes high variations of liver and renal markers. MMT achieves a stabilization of serum indicators relevant for methadone metabolism that correlates with the duration of consumption and the type of opioid substance. The most important hepato-renal markers as indicators of therapy success are γGT, LDH, and creatinine. The validity of former enzymatic tests (AST, ALP, and ALT) should be seriously reconsidered in terms of MTT treatment success and monitoring the health of heroin addicts.

Nasal administration of diacetylmorphine improved the adherence in a patient receiving heroin-assisted treatment.

BACKGROUND: Traditional heroin-assisted treatment in Switzerland consists of oral and injectable diacetylmorphine (pharmaceutical heroin) administration. To date, no suitable treatment option is available for patients who crave rapid onset ("rush") but are either unable to inject or primarily sniff or inhale illicit heroin. We present a patient who successfully switched to intranasal heroin-assisted treatment following several unsuccessful treatment attempts. CASE PRESENTATION: A 29-year-old male with severe opioid use disorder, injection substance use, and concomitant cocaine use, previously prescribed slow-release oral morphine, was started on intravenous diacetylmorphine. Due to complications and harms associated with intravenous injections, nasal diacetylmorphine was prescribed. With this novel route of administration, the patient who had previously been unable to adhere to other OAT options remained in treatment. Health outcomes improved by reduction of injection-related harms, increased adherence to the heroin-assisted treatment regimen, and increased collaboration with the therapeutic staff. CONCLUSIONS: Nasal heroin-assisted treatment can be a feasible therapeutic option for individuals with severe opioid use disorder who crave the fast onset of effect of diacetylmorphine but are unable to inject intravenously.

Heroin-assisted treatment of heroin-addicted patients normalizes regulatory T cells but does not restore CD4+ T cell proliferation.

Heroin dependence may result in suppression of adaptive immune responses. Previously, we demonstrated an increase in relative numbers of inhibitory CD4+ regulatory T cells (Tregs) and impaired proliferative activity of CD4+ T cells from heroin-addicted patients in contrast to patients in opioid maintenance therapy and healthy controls. However, it remains elusive whether heroin has a direct impact on the CD4+ T cell compartment or whether observed effects result from stressful living conditions. Here, we analyzed the frequencies of Tregs and the proliferation as well as the cytokine production of stimulated CD4+ T cells from heroin-addicted patients with use of illicit heroin, patients in heroin-assisted treatment (HAT), and patients in methadone maintenance therapy (MMT). Relative numbers of CD4+ Tregs were significantly enhanced in patients with illicit heroin abuse compared with patients in HAT or MMT. Notably, CD4+ T cells from patients in HAT and from persons using illicit heroin showed significant reduced proliferation and secretion of the pro-inflammatory cytokines IFN-γ and IL-6 upon stimulation in vitro. From these results, we conclude that structured programs such as HAT and MMT dampen elevated frequencies of Tregs in heroin-addicted patients, whereas chronic heroin administration irrespective of using illicit heroin or receiving HAT has a direct impact on the proliferative activity and cytokine production of CD4+ T cells.

Methadone-Assisted Opiate Withdrawal and Subsequent Heroin Abstinence: The Importance of Psychological Preparedness.

BACKGROUND AND OBJECTIVES: Treatment guidelines emphasize patients' readiness for transitioning from opiate substitution treatment (OST) to opiate withdrawal and abstinence. Psychological preparedness indicators for this transition were examined. METHODS: Patients (all male) were recruited from three treatment settings: prison, an inpatient detoxification unit, and an outpatient clinic. Time 1 (T1) was admission to methadone-assisted withdrawal in all settings. Time 2 (T2) was a 6-month follow-up. With n = 24 at T1 for each group (N = 72), a battery of instruments relevant to psychological preparedness was administered. RESULTS: At T1, inpatients had higher self-efficacy beliefs for successful treatment completion than prison patients. For patients contactable at T2, T1 self-efficacy positively predicted T2 opiate abstinence. No other variable improved prediction. T1 SOCRATES (Stages of Change Readiness and Treatment Eagerness Scale) ambivalence scores, age, and lifetime heroin use duration predicted maintenance of contact or not with treatment services and contactability by the researcher. Measures of mood did not differ between groups at T1 or predict T2 outcomes. DISCUSSION AND CONCLUSIONS: Self-efficacy beliefs are a potentially useful indicator of readiness for transitioning from OST to a medically assisted opiate withdrawal and subsequent abstinence. Ambivalence regarding change, age, and lifetime heroin use duration are potentially useful predictors of patients maintaining contact with services, and of being retained in research. SCIENTIFIC SIGNIFICANCE: These findings advance existing literature and knowledge by highlighting the importance of self-efficacy in psychological preparedness for opiate abstinence, and the predictive utility to clinicians of this and other variables measurable at admission, in the clinical management of opiate users. (© 2020 The Authors. The American Journal on Addictions published by Wiley Periodicals LLC on behalf of The American Academy of Addiction Psychiatry). (Am J Addict 2021;30:11-20).

«One prick and then it´s done¼: a mixed-methods exploratory study on intramuscular injection in heroin-assisted treatment.

BACKGROUND: Intramuscular (IM) injection of drugs is associated with high rates of injecting-related injuries and diseases. However, little is known about the role of this route of administration in heroin-assisted treatment. The aim of this study was to determine the prevalence of IM diacetylmorphine administration and associated complications as well as to explore patients' views and opinions on the topic and the underlying reasons for this practice. METHODS: The research site was a Swiss outpatient treatment centre specialised in heroin-assisted treatment. We conducted in-depth interviews with two patients who intramuscularly inject diacetylmorphine. Interviews were analysed qualitatively, and emerging themes were used to develop a 38-item questionnaire on IM injections. We then offered this questionnaire to all patients in the treatment centre. RESULTS: Five main themes emerged from the in-depth interviews: poor venous access, side effects, subjective effects, procedure for IM injection, and consideration of alternatives to IM. These themes covered the rationale for using this route of administration, complications, subjective effects of IM diacetylmorphine, hygiene and safety measures as well as alternative routes of administration. Fifty-three patients filled in the questionnaire. The lifetime prevalence of IM injections was 60.4% (n = 32) and 34.4% (n = 11) of the patients stated that IM injection was their primary route of administration. No participant reported using the IM route for street drugs. The main reason for IM injections was poor vein access. Other reasons given were time saving and less risk of injuries. Complications included induration of muscle tissue and pain, whereas more severe complications like thrombosis and infections of the injection site were reported much less often. CONCLUSION: As the population of opioid-dependent individuals is aging and the deterioration of access veins is likely to increase, the frequency of IM injecting will equally increase. Even though our data show that the IM injection of diacetylmorphine in a clinical setting is a common practice and appears to be relatively safe, research on alternative routes of administration is needed to provide potentially less harmful alternative routes of administration in heroin-assisted treatment.

[Learning to expand medical heroin prescribing modalities with Covid-19]. / Apprentissage de l'élargissement des modalités de prescription de l'héroïne médicale avec le Covid-19.

The choice of opioid-assisted treatments for patients with heroin dependence is particularly diverse in Switzerland. Since 1994, diacetylmorphine assisted treatments are available. The rules for prescribing and dispensing diacetylmorphine, as laid down by the FOPH, are particularly strict, requiring patients to attend the treatment center several times a day. Thanks to a legislative amendment by the Federal Council, it became possible to extend the dispensing of diacetylmorphine during the Covid-19 epidemic, allowing patients to take the treatment with them for longer periods and thus reducing the number of visits to the clinic. The time freed up could then be invested in other activities, allowing therapies to be refocused more on the patients' life project.

L'offre des traitements assistés par opioïdes pour les personnes avec dépendance à l'héroïne est particulièrement diversifiée en Suisse. Les traitements basés sur la prescription de diacétylmorphine y sont ainsi proposés depuis 1994, dont les règles de prescription et de remise au patient régies par l'Office fédéral de la santé publique sont particulièrement strictes, imposant aux patients un passage au centre de soins plusieurs fois par jour. Grâce aux modifications législatives du Conseil fédéral, permettant aux patients d'emporter le traitement pour des durées plus longues pendant la pandémie de Covid-19, les passages à la consultation ont été réduits. Cela a eu pour effet indirect de libérer du temps, qui a pu être investi dans d'autres activités, notamment le recentrage des thérapies davantage autour des projets de vie des patients.

Genetic polymorphisms in the opioid receptor delta 1 (OPRD1) gene are associated with methadone dose in methadone maintenance treatment for heroin dependence.

Delta opioid receptor (DOR) is well known to be involved in heroin dependence. This study tested the hypothesis that single nucleotide polymorphisms (SNPs) in the opioid receptor delta 1 (OPRD1) gene coding region are associated with treatment responses in a methadone maintenance therapy (MMT) cohort in Taiwan. Three hundred forty-four MMT patients were recruited. Diastolic/systolic blood pressure, heart rate, methadone dosage, and plasma concentrations of methadone were recorded. Twenty-five SNPs located within the OPRD1 genetic region were selected and genotyped from the genomic DNA of all 344 participants. After pairwise tagger analyses, tagger SNP rs204047 showed a significant association with methadone dosage (P = 0.0019), and tagger SNPs rs204047 and rs797397 were significantly associated with plasma R, S-methadone concentrations (P < 0.0006) in patients tested negative in the urine morphine test, which indicated patients with a better response to MMT. The major genotype carriers showed a higher methadone dosage and higher plasma concentrations of R, S-methadone than the minor genotype carriers. The results indicated that OPRD1 genetic variants were associated with methadone dosage and methadone plasma concentration in MMT patients with a negative morphine test result.

Naloxone-Induced Withdrawal in Individuals With and Without Fentanyl-Positive Urine Samples.

BACKGROUND AND OBJECTIVE: This retrospective analysis of data from heroin users screening for clinical research, sought to determine if more naloxone is needed to precipitate opioid withdrawal among those who regularly use heroin with fentanyl, as opposed to those who use heroin without fentanyl. METHODS: Over the course of three to five screening visits, participants completed assessments of drug use, along with urine toxicology tests at each visit. To test for opioid dependence, 29 participants completed a modified Wang test (score: 0-150) during which an intramuscular dose of naloxone (0.2-0.4 mg) was administered and the severity of withdrawal was quantified. RESULTS: The severity of opioid withdrawal was compared between individuals whose urine toxicology regularly tested positive for fentanyl (N = 15), and those only positive for other opioids (N = 14). No significant differences were found in demographic or drug use between the fentanyl-positive (mean: age 41.1 years, 9.1 bags heroin/d) and fentanyl-negative (42.0 years, 10.0 bags heroin/d) groups. Intramuscular naloxone-precipitated robust withdrawal in both samples (P < .01) with no significant difference (P = .8) in the severity (fentanyl positive [100.6 ± 13.4]; fentanyl negative [82.7 ± 9.6]). CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: These data suggest that a standard naloxone dose can be equally effective at precipitating withdrawal in individuals using heroin with fentanyl compared to heroin without fentanyl. These data contribute to our understanding of how naloxone antagonizes the effects of fentanyl and may have significant implications for the clinical laboratory and opioid overdose. A prospective clinical laboratory study with the proper opioid maintenance controls is needed to provide a more definitive finding. (Am J Addict 2019;00:00-00).