Pharmacotherapy for amphetamine dependence: A systematic review

20-year trends in Australian methamphetamine-related deaths, 2001-2020

BACKGROUND

Over the past two decades methamphetamine-related harms have increased in Australia. Previous analysis of methamphetamine-related deaths has covered limited timeframes, and largely focused on drug-toxicity deaths. This paper examines long-term trends in methamphetamine-related deaths over 20 years, including deaths due to a range of specific causes.

METHODS

Descriptive analyses were conducted on Australian methamphetamine-related deaths (2001-2023) by cause, extracted from the National Coronial Information System, an online database containing deaths reported to coroners in Australia and New Zealand. Joinpoint trend analyses were used to assess changes over time between 2001 and 2020 (with data from 2021 to 2023 likely incomplete and thus excluded).

RESULTS

Unintentional drug toxicity was the cause of 49.8 % of methamphetamine-related deaths, intentional self-harm (including toxicity) 23.3 %, unintentional injury 15.1 %, natural causes 9.6 %, and assaults 2.3 %. Between 2001 and 2020, joinpoint analysis showed three trend change points among all-cause methamphetamine-related mortality rates, resulting in four distinct periods: two periods where they increased (2001-2006 - annual percentage change (APC) = 15.4 %; 2009-2016 - APC 25.5 %), and two where they decreased (2006-2009 - APC = -11.8 %; 2017-2020 - APC = -2.9 %). Similar patterns were evident among rates of intentional self-harm and unintentional injury. Deaths caused by unintentional drug toxicity saw two trend change points (2011, 2016), and rates increased across all three periods. Natural cause deaths had three trend change points (2007, 2010, 2015), and rates continued to rise after 2015, largely driven by increases in circulatory diseases.

CONCLUSION

Cause-specific models highlighted diverse trends. Recent trends show unintentional drug toxicity deaths have slightly increased, intentional self-harm stabilised, and unintentional injury and assault deaths have declined. Deaths from natural causes involving methamphetamine continued to increase, highlighting a public health concern and a potential need for early circulatory disease screening among people who use methamphetamine.

Combining brief recall and ketamine treatment prevents stress-primed methamphetamine memory reinstatement via heightening mPFC GABA activity

This study aimed to assess whether brief recall of methamphetamine (MA) memory, when combined with ketamine (KE) treatment, may prevent stress-primed MA memory reinstatement. Combining 3-min recall and KE facilitated MA memory extinction and resistance to subsequent stress-primed reinstatement. Such combination also produced glutamate metabotropic receptor 5 (mGluR5) upregulation in animals' medial prefrontal cortex (mPFC) γ-amino-butyric acid (GABA) neuron. Accordingly, chemogenetic methods were employed to bi-directionally modulate mPFC GABA activity. Following brief recall and KE-produced MA memory extinction, intra-mPFC mDlx-Gi-coupled-human-muscarinic-receptor 4 (hM4Di)-infused mice receiving compound 21 (C21) treatment showed eminent stress-primed reinstatement, while their GABA mGluR5 expression seemed to be unaltered. Intra-mPFC mDlx-Gq-coupled-human-muscarinic-receptor 3 (hM3Dq)-infused mice undergoing C21 treatment displayed MA memory extinction and resistance to stress-provoked reinstatement. These results suggest that combining a brief recall and KE treatment and exciting mPFC GABA neuron may facilitate MA memory extinction and resistance to stress-primed recall. mPFC GABA neuronal activity plays a role in mediating brief recall/KE-produced effects on curbing the stress-provoked MA seeking.

Recommendation for Long-term Management of Adult Attention-Deficit/Hyperactivity Disorder in Military Populations, Veterans, and Dependents: A Narrative Review

INTRODUCTION

In addition to the higher burden of mental health disease in the military, there is a compounding antecedent association between behavioral health comorbidities and the treatment of attention-deficit/hyperactivity disorder (ADHD) in this population. Despite the low prevalence of new-onset ADHD in adults globally, the rate of stimulant (i.e., amphetamines) prescription is increasing. Stimulants can exacerbate mental health disease (often masquerading as ADHD symptomatology), precluding optimal treatment of the underlying etiology and imposing unnecessary dangerous side effects. This study aimed to evaluate the long-term safety and efficacy of stimulants for managing adult ADHD.

METHODS

A nine-member multidisciplinary team reviewed a PubMed search with the terms "adult," "ADHD," and "stimulant." Targeted PubMed and Google Scholar searches for "adult ADHD" paired with Food and Drug Administration -approved ADHD medications and Google Scholar literature using forward and reverse snowballing methods were performed for high-quality studies focusing on long-term treatment in ADHD. An evidence table and clinical algorithm were developed from the review.

RESULTS

Of the 1,039 results, 50 articles were fully reviewed, consisting of 21 descriptive and experimental studies, 18 observational, and 11 systematic reviews and meta-analyses. Illustrative cases within the structured discussion of the results highlighted ADHD and psychiatric comorbidities, risks, harms, and benefits of stimulant use, medication mechanisms of action, and limitations of the current evidence.

DISCUSSION

The dearth of high-quality studies on long-term ADHD management in adults fails to establish a causal relationship between stimulant use and physiological harm. Despite mixed evidence supporting the benefit of stimulants, there is clear evidence regarding the risk of harm. The serious risks of stimulants include arrhythmias, myocardial infarction, stroke/transient ischemic attack, sudden death, psychosis, and worsening of behavioral health disease. Additionally, there is a possible long-term risk of harm due to chronic sympathetic load (i.e., cardiovascular system remodeling). Stimulants pose a greater risk for addiction and abuse compared to other evidence-based nonstimulant medications that have similar effectiveness. Both stimulants and nonstimulants might promote favorable neuroanatomical changes for long-term improvement of ADHD symptoms, but nonstimulants (atomoxetine) have the pharmacological advantage of also mitigating the effects of sympathetic load (sympatholysis) and anxiety (anxiolysis). Given the physiological uncertainty of extended stimulant use for adults, especially older adults with vulnerable cardiovascular systems, clinicians should proceed cautiously when considering initiating or sustaining stimulant therapy. For long-term treatment of ADHD in adults, clinicians should consider nonstimulant alternatives (including behavioral therapy) due to the comparatively lower side effect risk and the possible additional benefit in patients with behavioral health comorbidities.

CONCLUSION

Long-term safety of stimulant use for adults with ADHD is uncertain, as existing studies are limited in quality and duration. This is particularly important for military populations with higher rates of mental health conditions. Managing ADHD and related conditions requires prioritizing cardiovascular safety, especially for older adults. Nonstimulant options can be helpful, especially in comorbid psychiatric disease. Before treating ADHD, ruling out and controlling other behavioral health conditions is essential to avoid masking or worsening underlying issues and reducing unnecessary medication side effects.

The ASAM/AAAP Clinical Practice Guideline on the Management of Stimulant Use Disorder

The American Society of Addiction Medicine/American Academy of Addiction Psychiatry (ASAM/AAAP) Clinical Practice Guideline on the Management of Stimulant Use Disorder provides guidance on evidence-based strategies for the treatment of stimulant use disorders (StUDs), stimulant intoxication, and stimulant withdrawal, as well as secondary and tertiary prevention of harms associated with stimulant use. The Clinical Guideline Committee (CGC) comprised experts from ASAM and AAAP representing a range of clinical settings and patient populations. The guideline was developed following modified GRADE methodology. The process included a systematic literature review as well as several targeted supplemental searches. The CGC utilized Evidence to Decision tables to review available evidence and rate the strength of each recommendation. The clinical practice guideline was revised based on external stakeholder review. Key takeaways included: Contingency management represents the current standard of care for treatment of StUDs; Pharmacotherapies may be utilized off-label to treat StUDs; Acute stimulant intoxication can result in life-threatening complications that should be addressed in an appropriate level of care; Secondary and tertiary prevention strategies should be used to reduce harms related to risky stimulant use.

Unveiling the Crucial Role of Chemical Enhancement in the SERS Analysis of Amphetamine-Metal Interactions on Gold and Silver Surfaces: Importance of Selective Amplification of the Narrow Interval of Vibrational Modes

The use of addictive substances, including drugs, poses significant health risks and contributes to various social problems, such as increased crime rates associated with substance-induced aggressive behavior. To address these challenges, possession of addictive substances is legally prohibited. However, detecting and analyzing these substances remain a complex task for law enforcement, primarily due to the presence of adulterants or limited sample quantities. In response to the evolving illicit market, continuous development and adaptation of analytical techniques are essential. One approach is the utilization of surface-enhanced Raman scattering (SERS) spectroscopy, which involves adsorbing the analyte onto nanostructured plasmonic surfaces. This study explores the potential of SERS in detecting amphetamine-based addictive stimulants with a specific focus on the properties of enhancing surfaces chosen. Comparative investigations were performed using silver and gold surfaces, with gold colloidal systems demonstrating a favorable performance. Moreover, to provide a comprehensive interpretation of the measured spectra, extensive density functional theory (DFT) calculations were conducted, allowing for a deeper understanding of the observed spectral features and molecular interactions with the metal surfaces. This review presents insights into the role of chemical enhancement in SERS analysis of amphetamine-metal interactions, shedding light on the selective amplification of vibrational modes. These findings, supported by DFT calculations, have implications in the fields of spectroscopy, physical chemistry, and drug analysis, providing valuable contributions to forensic applications and a deeper understanding of chemical enhancement phenomena. We present the impact of the secondary resonances of Stokes-scattered photons. This illustrates the significance of recognizing the constraints of the frequently employed "E4" approximation, even in measurements involving multiple molecules rather than single molecules.

Substance use and spine density: a systematic review and meta-analysis of preclinical studies

The elucidation of synaptic density changes provides valuable insights into the underlying brain mechanisms of substance use. In preclinical studies, synaptic density markers, like spine density, are altered by substances of abuse (e.g., alcohol, amphetamine, cannabis, cocaine, opioids, nicotine). These changes could be linked to phenomena including behavioral sensitization and drug self-administration in rodents. However, studies have produced heterogeneous results for spine density across substances and brain regions. Identifying patterns will inform translational studies given tools that now exist to measure in vivo synaptic density in humans. We performed a meta-analysis of preclinical studies to identify consistent findings across studies. PubMed, ScienceDirect, Scopus, and EBSCO were searched between September 2022 and September 2023, based on a protocol (PROSPERO: CRD42022354006). We screened 6083 publications and included 70 for meta-analysis. The meta-analysis revealed drug-specific patterns in spine density changes. Hippocampal spine density increased after amphetamine. Amphetamine, cocaine, and nicotine increased spine density in the nucleus accumbens. Alcohol and amphetamine increased, and cannabis reduced, spine density in the prefrontal cortex. There was no convergence of findings for morphine's effects. The effects of cocaine on the prefrontal cortex presented contrasting results compared to human studies, warranting further investigation. Publication bias was small for alcohol or morphine and substantial for the other substances. Heterogeneity was moderate-to-high across all substances. Nonetheless, these findings inform current translational efforts examining spine density in humans with substance use disorders.

Associations Between Buprenorphine\Naloxone and Methadone Treatment and non-Opioid Substance Use in Prescription-Type Opioid Use Disorder: Secondary Analyses From the OPTIMA Study: Associations entre le traitement avec la buprénorphine/naloxone et avec la méthadone et l'utilisation de substances non opioïdes dans le trouble lié à l'usage d'opioïdes de type sur ordonnance : analyses secondaires de l'étude OPTIMA

OBJECTIVES

There is limited evidence on how opioid agonist treatment (OAT) may affect psychoactive non-opioid substance use in prescription-type opioid use disorder (POUD) and whether this effect might explain OAT outcomes. We aimed to assess the effect of methadone on non-opioid substance use compared to buprenorphine/naloxone (BUP/NX), to explore whether non-opioid substance use is associated with opioid use and retention in treatment, and to test non-opioid use as a moderator of associations between methadone with retention in OAT and opioid use compared to BUP/NX.

METHODS

This is a secondary analysis of data from the OPTIMA trial, an open-label, pragmatic, parallel, two-arm, pan-Canadian, multicentre, randomized-controlled trial to compare standard methadone model of care and flexible take-home dosing BUP/NX for POUD treatment. We studied the effect of methadone and BUP/NX on non-opioid substance use evaluated by urine drug screen (UDS) and by classes of non-opioid substances (i.e., tetrahydrocannabinol [THC], benzodiazepines, stimulants) (weeks 2-24) using adjusted generalized estimation equation (GEE). We studied the association between non-opioid substance-positive UDS and opioid-positive UDS and retention in treatment, using adjusted GEE and logistic regressions.

RESULTS

Overall, methadone was not associated with non-opioid substance-positive UDS compared to BUP/NX (OR: 0.78; 95%CI, 0.41 to 1.48). When non-opioid substances were studied separately, methadone was associated with lower odds of benzodiazepine-positive UDS (OR: 0.63; 95% CI: 0.40 to 0.98) and THC-positive UDS (OR: 0.47; 95% CI: 0.28 to 0.77), but not with different odds of stimulant-positive UDS (OR: 1.29; 95% CI: 0.78 to 2.16) compared to BUP/NX. Substance-positive UDS, overall and separate classes, were not associated with opioid-positive UDS or retention in treatment.

CONCLUSION

Methadone did not show a significant effect on overall non-opioid substance use in POUD compared to BUP/NX treatment but was associated with lower odds of benzodiazepine and THC use in particular. Non-opioid substance use did not predict OAT outcomes. Further research is needed to ascertain whether specific patterns of polysubstance use (quantity and frequency) may affect treatment outcomes.

Prescription psychostimulants for the treatment of amphetamine-type stimulant use disorder: A systematic review and meta-analysis of randomized placebo-controlled trials

BACKGROUND AND AIMS

There is currently no standard of care for pharmacological treatment of amphetamine-type stimulant (ATS) use disorder (ATSUD). This systematic review with meta-analysis (PROSPERO CRD42022354492) aimed to pool results from randomized placebo-controlled trials (RCTs) to evaluate efficacy and safety of prescription psychostimulants (PPs) for ATSUD.

METHODS

Major indexing sources and trial registries were searched to include records published before 29 August 2022. Eligible studies were RCTs evaluating efficacy and safety of PPs for ATSUD. Risk of bias (RoB) was assessed using the Cochrane RoB 2 tool. Risk ratio (RR) and risk difference were calculated for random-effect meta-analysis of dichotomous variables. Mean difference and standardized mean difference (SMD) were calculated for random-effect meta-analysis of continuous variables.

RESULTS

Ten RCTs (n = 561 participants) were included in the meta-analysis. Trials studied methylphenidate (n = 7), with daily doses of 54-180 mg, and dextroamphetamine (n = 3), with daily doses of 60-110 mg, for 2-24 weeks. PPs significantly decreased end-point craving [SMD  -0.29; 95% confidence interval (CI) = -0.55, -0.03], while such a decrease did not reach statistical significance for ATS use, as evaluated by urine analysis (UA) (RR = 0.93; 95% CI = 0.85-1.01). No effect was observed for self-reported ATS use, retention in treatment, dropout following adverse events, early-stage craving, withdrawal and depressive symptoms. In a sensitivity analysis, treatment was associated with a significant reduction in UA positive for ATS (RR = 0.89; 95% CI = 0.79-0.99) after removing studies with a high risk of bias. In subgroup analyses, methylphenidate and high doses of PPs were negatively associated with ATS use by UA, while higher doses of PPs and treatment duration (≥ 20 weeks) were positively associated with longer retention.

CONCLUSIONS

Among individuals with amphetamine-type stimulant use disorder, treatment with prescription psychostimulants may decrease ATS use and craving. While effect size is limited, it may increase with a higher dosage of medications.

Bupropion for treatment of amphetamine-type stimulant use disorder: A systematic review and meta-analysis of placebo-controlled randomized clinical trials

BACKGROUND

This meta-analysis (PROSPERO-ID: CRD42022362962), pooled effect estimates of outcomes, from placebo-controlled randomized clinical trials (RCTs) examining bupropion efficacy and safety for amphetamine-type stimulant use disorder (ATSUD) treatment.

METHOD

Electronic databases were searched for records published to October 31st, 2022, including MEDLINE, CINAHL, PsycINFO, EBM Reviews, EMBASE, PubMed, Web of Science, trial registries. Inclusion criteria were RCTs comparing bupropion to placebo in ATSUD. Cochrane RoB2 tool and GRADE evidence certainty assessment were employed. Outcomes included amphetamine-type stimulant (ATS) use by urinalysis, retention in treatment, treatment adherence, ATS craving, addiction severity, depressive symptom severity, drop-out following adverse events (AEs), and serious AEs. Random-effect meta-analysis was conducted presenting standardized mean difference (SMD), risk ratio (RR), and risk difference (RD).

RESULTS

Eight RCTs (total N=1239 participants) were included. Bupropion compared to placebo was associated with reduced ATS use (RR: 0.90; 95% CI: 0.84, 0.96), end-of-treatment ATS craving (SMD: -0.38; 95%CI: -0.63, -0.13), and adherence (RR: 0.91; 95%CI: 0.84, 0.99). Subgroup analysis showed greater reduction in ATS use with longer trial duration (12 weeks) (RR: 0.85; 95%CI: 0.78, 0.93) and greater reduction in end-of-treatment ATS craving in studies with mixed ATS use frequency (SMD: -0.46; 95%CI: -0.70, -0.22) and male-only samples (SMD: -1.26; 95%CI: -1.87, -0.65).

CONCLUSION

Bupropion showed a significant modest reduction in ATS use and ATS craving (both rated as very low-quality evidence), larger in males (craving), and with longer treatment (ATS use). These results may inform future studies. More research is warranted on who might benefit from bupropion as ATSUD treatment.

Navigating Evidence, Challenges, and Caution in the Treatment of Stimulant Use Disorders

Amidst the opioid epidemic, harm reduction-oriented approaches have gained traction, including interventions that focus on prescribing pharmaceutical-grade psychoactive substances, such as opioids, instead of illicit versions, intending to mitigate fatal overdose risks arising from the variability in potency and additives found in illicit drugs. Stimulants have increasingly been found in the victims of opioid overdoses, further prompting some to argue for the prescription of stimulant medications for individuals with stimulant use disorders. Yet, the evidence supporting this practice remains insufficient. In this communication, we critically examine the existing evidence, challenges, and cautions surrounding the treatment of stimulant use disorder.

Methylphenidate as a treatment option for substance use disorder: a transdiagnostic perspective

A transition in viewing mental disorders from conditions defined as a set of unique characteristics to one of the quantitative variations on a collection of dimensions allows overlap between disorders. The overlap can be utilized to extend to treatment approaches. Here, we consider the overlap between attention-deficit/hyperactivity disorder and substance use disorder to probe the suitability to use methylphenidate as a treatment for substance use disorder. Both disorders are characterized by maladaptive goal-directed behavior, impaired cognitive control, hyperactive phasic dopaminergic neurotransmission in the striatum, prefrontal hypoactivation, and reduced frontal cortex gray matter volume/density. In addition, methylphenidate has been shown to improve cognitive control and normalize associated brain activation in substance use disorder patients and clinical trials have found methylphenidate to improve clinical outcomes. Despite the theoretical basis and promising, but preliminary, outcomes, many questions remain unanswered. Most prominent is whether all patients who are addicted to different substances may equally profit from methylphenidate treatment.

The Alkylamine Stimulant 1,3-Dimethylamylamine Exhibits Substrate-Like Regulation of Dopamine Transporter Function and Localization

The alkylamine stimulant 1,3-dimethylamylamine (DMAA) is used nonmedically as an appetite suppressant and exercise performance enhancer despite adverse cardiovascular effects that have limited its legal status. There is scant research describing the mechanism of action of DMAA, making it difficult to gauge risks or therapeutic potential. An important molecular target of structurally related phenethylamines, such as amphetamine, for regulating mood, cognition, movement, and the development of substance use disorder is the dopamine transporter, which limits the range and magnitude of dopamine signaling via reuptake from the extracellular space. The present studies were therefore initiated to characterize the effects of DMAA on dopamine transporter function. Specifically, we tested the hypothesis that DMAA exhibits substrate-like effects on dopamine transporter function and trafficking. In transport assays in human embryonic kidney cells, DMAA inhibited dopamine uptake by the human dopamine transporter in a competitive manner. Docking analysis and molecular dynamics simulations supported these findings, revealing that DMAA binds to the S1 substrate binding site and induces a conformational change from outward-facing open to outward-facing closed states, similar to the known substrates. Further supporting substrate-like effects of DMAA, the drug stimulated dopamine transporter endocytosis in a heterologous expression system via cocaine- and protein kinase A-sensitive mechanisms, mirroring findings with amphetamine. Together, these data indicate that DMAA elicits neurologic effects by binding to and regulating function of the dopamine transporter. Furthermore, pharmacologic distinctions from amphetamine reveal structural determinants for regulating transporter conformation and add mechanistic insight for the regulation of dopamine transporter endocytosis. SIGNIFICANCE STATEMENT: The alkylamine stimulant 1,3-dimethylamylamine (DMAA) is used as an appetite suppressant and athletic performance enhancer and is structurally similar to amphetamine, but there is scant research describing its mechanism of action. Characterizing the effects of DMAA on dopamine transporter function supports evaluation of potential risks and therapeutic potential while also revealing mechanistic details of dynamic transporter-substrate interactions.

Amphetamine-induced prolonged disturbances in tissue levels of dopamine and serotonin in the rat brain

BACKGROUND

A hallmark of psychostimulants is the persistence of neurobiological changes they produce. The difficulty in reversing long-time effects of psychostimulants use is why addiction therapy is so ineffective. This study aimed to look for such drug-induced changes that can be detected even after many weeks of abstinence.

METHODS

Rats were given 12 doses of amphetamine (Amph) at 1.5 mg/kg. The rewarding effect of Amph was assessed using ultrasonic vocalization. After 14 and 28 days of abstinence, tissue levels of dopamine (DA), serotonin (5-HT), and their metabolites were measured in the prefrontal cortex (PFC), nucleus accumbens (Acb), dorsomedial (CPuM), and dorsolateral (CPuL) striatum.

RESULTS

After 28 days of abstinence, DA levels were increased in the dorsal striatum while 5-HT levels were decreased in all brain regions studied. The opposite direction of changes in DA and 5-HT tissue levels observed in the dorsal striatum may be related to the changes in the emotional state during abstinence and may contribute to the incubation of craving and relapses. Tissue levels of 5-HT and DA showed intra- and inter-structural correlations, most pronounced after 14 days of abstinence. Most of them were absent in the control group (ctrl), which may indicate that their appearance was related to the changes induced by earlier Amph administration. We did not find any associations between reward sensitivity and the persistence of Amph-induced neurochemical disturbances.

CONCLUSIONS

Administration of 12 moderate doses of Amph causes prolonged changes in DA and 5-HT tissue levels. The direction and severity of the changes are dependent on the brain region and the neurotransmitter studied.

Health and social characteristics of clients reporting amphetamine type substance use at entry to public alcohol and other drug services in New South Wales, Australia, 2016-2019

INTRODUCTION

Amphetamine type substances (ATS) are commonly used by Australian alcohol and other drug service entrants. We describe demographic characteristics, patterns of ATS and other substance use, health and social conditions among clients entering New South Wales (NSW) public alcohol and other drug services.

METHODS

Retrospective cohort of 13,864 records across six health districts (2016-2019) for clients seeking substance use treatment. These districts service approximately 44% of the NSW population aged 15 years and over. Multivariate analysis was conducted on a subsample for whom full data were available (N = 9981). Data included NSW Minimum Data Set for drug and alcohol treatment services and Australian Treatment Outcomes Profile items.

RESULTS

Over the preceding 4 weeks, 77% (n = 10,610) of clients (N = 13,864) reported no recent ATS use, 15% (n = 2109) reported 'low frequency' (1-12 days) and 8% (n = 1145) 'high frequency' (13-28 days) use. ATS use was most common among people attending for ATS or opioids as primary drug of concern. A multinomial regression (N = 9981) identified that clients reporting recent arrest (aOR 1.74, 95% CI 1.36, 2.24), higher cannabis use frequency (aOR 1.01, 95% CI 1.00, 1.02), lower opioid use frequency (aOR 0.98, 95% CI 0.97, 0.99) and poorer quality of life (aOR 0.91, 95% CI 0.86, 0.97) were more likely to report 'high frequency' rather than 'low frequency' ATS use.

DISCUSSION AND CONCLUSIONS

People who use ATS experience health and social issues that may require targeted responses. These should be integrated across all services, not only for clients with ATS as principal drug of concern.

Noninvasive Vagus Nerve Stimulation in the Treatment of Methamphetamine Use Disorder: A Review Article

: Methamphetamine (MA) use and the mortality it causes are increasing worldwide. The neurobiological mechanisms underlying the destructive effects of MA use are complex; however, there is much evidence that MA induces the dysfunction of monoaminergic transmission and causes oxidative stress, neuroinflammation, gliosis, and apoptosis. These toxic effects are associated with cardiotoxicity and neurotoxicity and with an imbalance in the autonomic nervous system, which altogether manifest themselves in clinical symptoms, such as neuropsychiatric disorders and cardiovascular diseases. There is no approved treatment for methamphetamine use disorder (MUD) despite all efforts made to date. The behavioral and pharmacological approaches currently used for the treatment of MUD are not completely effective. In this study, it is hypothesized that the stimulation of the vagus nerve and biological pathways underlying the processes of this stimulation might be effective as adjunctive therapy. Despite the potential effects of vagus nerve stimulation (VNS) to improve MUD, no study has yet examined the clinical potential effects of VNS in patients with the disorder. Therefore, further studies, including experimental and clinical trials, are needed to examine the effects of VNS on MUD.

Characterising methamphetamine use to inform health and social policies in Manitoba, Canada: a protocol for a retrospective cohort study using linked administrative data

INTRODUCTION

Rising use of methamphetamine is causing significant public health concern in Canada. The biological and behavioural effects of methamphetamine range from wakefulness, vigour and euphoria to adverse physical health outcomes like myocardial infarction, haemorrhagic stroke, arrhythmia and seizure. It can also cause severe psychological complications such as psychosis. National survey data point to increasing rates of methamphetamine use, as well as increasing ease of access and serious methamphetamine-related harms. There is an urgent need for evidence to address knowledge gaps, provide direction to harm reduction and treatment efforts and inform health and social policies for people using methamphetamine. This protocol describes a study that aims to address this need for evidence.

METHODS

The study will use linked, whole population, de-identified administrative data from the Manitoba Population Research Data Repository. The cohort will include individuals in the city of Winnipeg, Manitoba, who came into contact with the health system for reasons related to methamphetamine use from 2013 to 2021 and a comparison group matched on age, sex and geography. We will describe the cohort's sociodemographic characteristics, calculate incidence and prevalence of mental disorders associated with methamphetamine use and examine rates of health and social service use. We will evaluate the use of olanzapine pharmacotherapy in reducing adverse emergency department outcomes. In partnership with Indigenous co-investigators, outcomes will be stratified by First Nations and Métis identity.

ETHICS AND DISSEMINATION

The study was approved by the University of Manitoba Health Research Ethics Board, and access datasets have been granted by all data providers. We also received approval from the First Nations Health and Social Secretariat of Manitoba's Health Information Research Governance Committee and the Manitoba Métis Federation. Dissemination will be guided by an 'Evidence 2 Action' group of public rightsholders, service providers and knowledge users who will ensure that the analyses address the critical issues.

Tactile Stimulation in Adult Rats Modulates Dopaminergic Molecular Parameters in the Nucleus accumbens Preventing Amphetamine Relapse

Amphetamine (AMPH) is a psychostimulant drug frequently related to addiction, which is characterized by functional and molecular changes in the brain reward system, favoring relapse development, and pharmacotherapies have shown low effectiveness. Considering the beneficial influences of tactile stimulation (TS) in different diseases that affect the central nervous system (CNS), here we evaluated if TS applied in adult rats could prevent or minimize the AMPH-relapse behavior also accessing molecular neuroadaptations in the nucleus accumbens (NAc). Following AMPH conditioning in the conditioned place preference (CPP) paradigm, male rats were submitted to TS (15-min session, 3 times a day, for 8 days) during the drug abstinence period, which were re-exposed to the drug in the CPP paradigm for additional 3 days for relapse observation and molecular assessment. Our findings showed that besides AMPH relapse, TS prevented the dopamine transporter (DAT), dopamine 1 receptor (D1R), tyrosine hydroxylase (TH), mu opioid receptor (MOR) increase, and AMPH-induced delta FosB (ΔFosB). Based on these outcomes, we propose TS as a useful tool to treat psychostimulant addiction, which is subsequent to clinical studies; it could be included in detoxification programs together with pharmacotherapies and psychological treatments already conventionally established.

Different phases of ATS use call for different interventions: a large qualitative study in Europe

BACKGROUND

Amphetamine-type stimulants (ATS) are globally widely used. Scientific literature generally defines four phases of substance use (initiation, continuation, increase and decrease); however, there is limited understanding of what influences these different phases of ATS use. The ATTUNE study investigated which factors shape individual phases of use, or ATS use patterns. In this article, we report on these phases into and out of ATS use, and propose a set of recommendations for prevention, harm reduction and treatment of the different phases of ATS use.

METHODS

Qualitative, semi-structured interviews (n = 237) were conducted in five different European countries with participants who had used ATS, varying from a few times in a lifetime to daily.

RESULTS

Amphetamine and MDMA were the most commonly used ATS. Yet, types of ATS used differed between the countries. We found that people who use ATS have various motives for and dynamic patterns of ATS use with alternating phases of increase, continuation, decrease and sometimes dependence. Cessation was pursued in different ways and for diverse reasons, such as mental health problems and maturing out. Availability seemed not an issue, regardless of the type of ATS, phase or country.

CONCLUSIONS

These findings demonstrate that tailor-made interventions are needed for the diverse types of people who use ATS and different phases or patterns of ATS use, to reduce possible harms of use. We recommended a set of interventions for the different ATS phases. These include drug checking services, peer-led information, self-management of ATS use, mental health support to help people cope with stressful life events and prevent uncontrolled use, and follow-up support after treatment.

Amphetamine-Type Stimulant Dependence and Association with Concurrent Use of Cocaine, Alcohol, and Cannabis: A Cross-Sectional Study

INTRODUCTION

Amphetamine-type stimulants (ATSs) are the second most commonly used class of illegal substances in Europe. Although concurrent substance use has been subject to research, little is known about associations between concurrent use of cocaine, alcohol, or cannabis and ATS dependence. We expect that the concurrent use of any of the substance, especially cannabis and cocaine, is associated with ATS dependence.

METHODS

Cross-sectional data were gathered within the European ATTUNE study in 2018/2019. Participants (N = 721) were asked about their consumption patterns and social, psychological, and economic situation. Multivariate logistic regressions were carried out for associations between ATS dependence and use combinations of frequent cocaine, alcohol, or cannabis, with the reference group of no frequent concurrent use (model 1). Model 2 calculated associations for ATS dependence with lifetime methamphetamine use for respective use combinations.

RESULTS

The study population was on average 28.9 years old (SD = 7.7), with the majority being male (63.5%). In model 1, the adjusted odds ratio (aOR) for frequent alcohol use was 0.70 (confidence interval [CI] 0.41-1.20). Similar results were shown for model 2 (aOR 0.82, CI 0.42-1.62). Frequent cannabis use significantly reduced the chance for ATS dependence by 50% in adjusted model 1 (aOR 0.50, CI 0.28-0.89) and by 62% in model 2 (aOR 0.38, CI 0.18-0.82). For frequent cocaine use, models 1 and 2 report an aOR at 1.37 (CI 0.58-3.25) and 2.39 (CI 0.77-7.43), although not statistically significant. Frequent users of all 3 substances had a significant 3-fold chance for ATS dependence (model 1: aOR 2.98, CI 1.16-7.63; model 2: aOR 2.95, CI 1.02-8.58).

DISCUSSION

Against initial hypotheses, frequent concurrent use of alcohol or cannabis generally decreased chances for ATS dependence. An explanation could be the study population, which consists of many irregular users of ATS, who mainly consume alcohol or cannabis. Cocaine generally increased chances, although results were not significant. The frequent use of all 3 substances together with ATS in the last year was significantly associated with dependence, thus reporting important information for treatment services. Further research is needed for disentangling causal relationships underlying these associations and for pinpointing consequences for relapse prevention and retention success.

A systematic literature review of clinical trials and therapeutic applications of ibogaine

BACKGROUND

Iboga and its primary alkaloids, ibogaine and noribogaine, have been of interest to researchers and practitioners, mainly due to their putative efficacy in treating substance use disorders (SUDs). For many SUDs, still no effective pharmacotherapies exist. Distinct psychoactive and somatic effects of the iboga alkaloids set them apart from classic hallucinogens like LSD, mescaline, and psilocybin.

AIMS

The study team performed this systematic review focusing on clinical data and therapeutic interventions involving ibogaine and noribogaine.

METHODS

The team conducted a search for all publications up to December 7, 2020, using PubMed and Embase following PRISMA guidelines.

RESULTS

In total, we identified 743 records. In this review, we consider 24 studies, which included 705 individuals receiving ibogaine or noribogaine. This review includes two randomized, double-blind, controlled clinical trials, one double-blind controlled clinical trial, 17 open-label studies or case series (including observational or retrospective studies), three case reports, and one retrospective survey. The published data suggest that ibogaine is an effective therapeutic intervention within the context of SUDs, reducing withdrawal symptoms and craving. Data also point toward a beneficial impact on depressive and trauma-related psychological symptoms. However, studies have reported severe medical complications and deaths, which seem to be associated with neuro- and cardiotoxic effects of ibogaine. Two of these fatalities were described in the 24 studies included in this review.

CONCLUSION

Treatment of SUDs and persisting comorbidities requires innovative treatment approaches. Rapid-onset therapies such as the application of ibogaine may offer novel treatment opportunities for specific individuals. Rigorous study designs within medical settings are necessary to warrant safe application, monitoring, and, possibly, medical intervention.

The role of glucagon-like peptide 1 (GLP-1) in addictive disorders

Drug-, alcohol- and tobacco use disorders are a global burden affecting millions of people. Despite decades of research, treatment options are sparse or missing, and relapse rates are high. Glucagon-like peptide-1 (GLP-1) is released in the small intestines, promotes blood glucose homeostasis, slows gastric emptying, and reduces appetite. GLP-1 receptor agonists approved for treating type 2 diabetes mellitus and obesity, have received attention as a potential anti-addiction treatment. Studies in rodents and non-human primates have demonstrated a reduction in intake of alcohol and drugs of abuse, and clinical trials have been initiated to investigate whether the preclinical findings can be translated to patients. This review will give an overview of current findings and discuss the possible mechanisms of action. We suggest that effects of GLP-1 in alcohol- and substance use disorder is mediated centrally, at least partly through dopamine signalling, but precise mechanisms are still to be uncovered.

Methamphetamine and sleep impairments: neurobehavioral correlates and molecular mechanisms

Methamphetamine is a potent and highly addictive psychostimulant, and one of the most widely used illicit drugs. Over recent years, its global usage and seizure have been on a rapid rise, with growing detrimental effects on mental and physical health, and devastating psychosocial impact pressing for intervention. Among the unwanted effects of methamphetamine, acute and long-term sleep impairments are of major concern, posing a significant therapeutic challenge, and a cause of addiction relapse. Unraveling mechanisms and functional correlates of methamphetamine-related sleep and circadian disruption are, therefore, of key relevance to translational and clinical psychiatry. In this article, we review the mounting evidence for the acute and long-term impairements of sleep-wake behavior and circadian activity caused by single or recurring methamphetamine usage and withdrawal. Factors contributing to the severity of sleep loss and related cognitive deficit, with risks of relapse are discussed. Key molecular players mediating methamphetamine-induced dopamine release and neuromodulation are considered, with wake-promoting effects in mesolimbic circuits. The effects on various sleep phases and related changes in dopamine levels in selected subcortical structures are reviewed and compared to other psychostimulants with similar action mechanisms. A critical appraisal is presented of the therapeutic use of modafinil, countering sleep, and circadian rhythm impairments. Finally, emerging knowledge gaps and methodical limitations are highlighted along with the areas for future research and therapeutic translation.

Psychosocial Interventions for Amphetamine Type Stimulant Use Disorder: An Overview of Systematic Reviews

Introduction: Amphetamine-type stimulants (ATS) use is a global concern due to increased usage and the harm to physical, mental, and social well-being. The objective of this overview of systematic reviews is to summarise trial results of psychosocial interventions and describe their efficacy and safety. Methods: We searched seven bibliographic databases to November 2020 for systematic reviews examining ATS misuse treatment by psychosocial interventions. Given the apparent incompleteness of the included reviews, we undertook a supplemental meta-analysis of all eligible primary studies. Results: We included 11 systematic reviews of moderate to high quality and 39 primary studies which assessed the outcomes of psychosocial interventions on people who use ATS. The key findings include: (1) There were conflicting results about the effectiveness of psychosocial interventions among reviews, which may confuse decision-makers in selecting treatment. (2) In the supplemental meta-analysis, relative to usual care (only counselling or self-help materials), membership of a psychological intervention group was associated with an important reduction in drug usage [risk ratio (RR) 0.80, 95% CI: 0.75 to 0.85]. Patients in psychological interventions used injectables substantially less [odds ratio (OR) 0.35, 95% CI: 0.24 to 0.49]. The risk of unsafe sex in the psychosocial intervention group was lower than in the control group (RR 0.49, 95% CI: 0.34 to 0.71). The combination of therapies reduced 1.51 day using drugs in the preceding 30 days (95% CI: -2.36 to -0.67) compared to cognitive behavioural therapy intervention alone. (3) Compared to usual care, cognitive behavioural therapy was less likely to be retained at follow-up (RR 0.89, 95% CI: 0.82 to 0.97; high-quality evidence). However, the additional of contingency management strategy can make an important improvement upon retention (RR 1.42, 95%CI: 1.25 to 1.62). Authors' Conclusions: Integrated models are more effective than a single-treatment strategy. Comprehensive and sustained psychosocial interventions can help to reduce use of ATS and other drugs, risk behaviours and mental disorders, and significantly improve treatment adherence.

Research progress of berberine mediated photodynamic therapy

Berberine (BBR) is a plant secondary metabolite that has been used in photodynamic therapy (PDT) in the last few decades. The present review aimed to discuss the research progress of BBR-mediated photodynamic actions. The following key words were searched in several databases: 'Berberine' combined with 'photodynamic therapy', 'sonodynamic therapy (SDT)', 'ultraviolet', 'reactive oxygen' and 'singlet oxygen'. The results demonstrated that both type I and type II reactions participated in the photodynamic progression of BBR derivatives. In addition, the photochemical characteristics of BBR derivatives were affected by the polarity, pH and O2 content of solvents. DNA binding increases the lifespan of the photoexcited BBR state and generation of singlet oxygen (1O2). The chemical properties of substituents in different positions of the BBR skeleton are pivotal for its photochemical properties, particularly the methylenedioxy group at the C-2 and C-3 positions. BBR is a promising agent for mediating both PDT- and SDT-treated diseases, particularly in tumors. However, further studies are required to validate their biological effects. In addition, the molecular mechanisms underlying the antitumor effects of BBR-PDT remain unclear and warrant further investigation. The structural modification and targeted delivery of BBR have made it possible to broaden its applications; however, experimental verification is required. Overall, BBR acts as a sensitizer for PDT and has promising development prospects.

Mandatory treatment for methamphetamine use in Australia

Background

In 2016, following a flurry of government inquiries and taskforces including calls for mandatory treatment regimes, the Australian community nominated methamphetamine as the drug most likely to be associated as a problem substance. Mandatory treatment for alcohol and other drug problems in Australia consists of broadly two mechanisms compelling a person into treatment: involuntary treatment or civil commitment regimes; and coercive treatment regimes, usually associated with the criminal justice system. This paper aims to provide a review of the evidence for mandatory treatment regimes for people who use methamphetamines.

Methods

Using a narrative review methodology, a comprehensive literature and citation search was conducted. Five hundred two search results were obtained resulting in 41 papers that had cited works of interest.

Results

Small, but robust results were found with coercive treatment programs in the criminal justice system. The evidence of these programs specifically with methamphetamine use disorders is even less promising. Systematic reviews of mandatory drug treatment regimes have consistently demonstrated limited, if any, benefit for civil commitment programs. Despite the growing popular enthusiasm for mandatory drug treatment programs, significant clinical and ethical challenges arise including determining decision making capacity in people with substance use disorders, the impact of self determination and motivation in drug treatment, current treatment effectiveness, cost effectiveness and unintended treatment harms associated with mandatory programs.

Conclusion

The challenge for legislators, service providers and clinicians when considering mandatory treatment for methamphetamines is to proportionately balance the issue of human rights with effectiveness, safety, range and accessibility of both existing and novel mandatory treatment approaches.

Targeting mGlu5 for Methamphetamine Use Disorder

Methamphetamine abuse leads to devastating consequences, including addiction, crime, and death. Despite decades of research, no medication has been approved by the U.S. Food and Drug Administration for the treatment of Methamphetamine Use Disorder. Thus, there is a need for new therapeutic approaches. Animal studies demonstrate that methamphetamine exposure dysregulates forebrain function involving the Group-I metabotropic glutamate receptor subtype 5 (mGlu₅), which is predominantly localized to postsynaptic sites. Allosteric modulators of mGlu₅ offer a unique opportunity to modulate glutamatergic neurotransmission selectively, thereby potentially ameliorating methamphetamine-induced disruptions. Negative allosteric modulators of mGlu₅ attenuate the effects of methamphetamine, including rewarding/reinforcing properties of the drug across animal models, and have shown promising effects in clinical trials for Anxiety Disorder and Major Depressive Disorder. Preclinical studies have also sparked great interest in mGlu₅ positive allosteric modulators, which exhibit antipsychotic and anxiolytic properties, and facilitate extinction learning when access to methamphetamine is removed, possibly via the amelioration of methamphetamine-induced cognitive deficits. Clinical research is now needed to elucidate the mechanisms underlying the mGlu₅ receptor-related effects of methamphetamine and the contributions of these effects to addictive behaviors. The growing array of mGlu₅ allosteric modulators provides excellent tools for this purpose and may offer the prospect of developing tailored and effective medications for Methamphetamine Use Disorder.

Interest in reducing methamphetamine and opioid use among syringe services program participants in Washington State

BACKGROUND

Methamphetamine use is increasing, and opioid use remains elevated in the US. Understanding interest in reducing/stopping substance use among people who inject drugs (PWID), as well as types of help wanted, can inform interventions.

METHODS

Data from the 2019 Washington State Syringe Exchange Survey were used in logistic regression analyses to assess if demographics, substance use, and concern about anxiety or depression were associated with interest in reducing/stopping substance use among people whose main drug was methamphetamine or opioids. Types of help wanted to reduce/stop use are reported.

RESULTS

Of 583 participants included, 76 % reported opioids were their main drug, of whom 82 % were interested in reducing/stopping their opioid use. 24 % reported methamphetamine as their main drug, of whom 46 % were interested in reducing/stopping their methamphetamine use. Among those whose main drug was an opioid, female gender (AOR:2.19, p = .023) and concern about depression (AOR:3.04, p = .002) were associated with interest in reducing/stopping opioid use. Among participants whose main drug was methamphetamine, being in jail in the past year and having an infection likely related to injection (e.g., abscess) in the past year were associated with over twice the odds of interest in reducing/stopping methamphetamine use (AOR:2.14, p = .056 and 2.43, p = .052, respectively); however, these findings were not significant. Several types of help to reduce/stop use were endorsed.

CONCLUSION

There were high, though differing, levels of interest in reducing/stopping opioid or methamphetamine use and in a range of support services. PWID should be asked about interest in reducing/stopping use and provided appropriate support.

The therapeutic effects of methylphenidate and matrix-methylphenidate on addiction severity, craving, relapse and mental health in the methamphetamine use disorder

Background

Little evidence has examined the therapeutic effects of methylphenidate (MPH) and Matrix Model treatment on addiction severity, craving, relapse and mental health in people who use methamphetamine (PWUM). This study was conducted to determine the effects of MPH, Matrix Model treatment, and Matrix-MPH on addiction severity, craving, relapse and mental health in PWUM.

Methods

This clinical trial was conducted among 100 patients with METH users. Participants were randomly divided into four groups who received: 1) 22 sessions of 45-min, twice a week for Matrix Model treatment (n = 25); 2) MPH 10 mg/day in the first month, 7.5 mg/day in the second month and 5 mg/day in the third month (n = 25); 3) Matrix Model treatment combined with MPH (n = 25); 4) control group (n = 25) for 12 weeks. Addiction severity, craving, relapse and mental status were evaluated at baseline and end-of-trial.

Results

Matrix Model treatment combined with MPH significantly reduced MA craving (P < 0.001) and addiction severity (P < 0.001). In addition, Matrix Model treatment combined with MPH resulted in a significant increase of mental health (P = 0.001), compared with Matrix Model treatment, MPH, and control group. Also, negative METH urine test significantly increased in the Matrix Model treatment combined with MPH group compared with the other groups (P < 0.001).

Conclusions

In conclusion, Matrix Model treatment combined with MPH for 12 weeks had beneficial effects on addiction severity, craving, relapse, and mental health in PWUM, compared with Matrix Model treatment, MPH, and control group.

Trial registration

This study was retrospectively registered in the Iranian website (www.irct.ir) for clinical trials registration (http://www.irct.ir: IRCT20171105037245N1). Registration date: 9 December 2017.

Neurobiology, Clinical Presentation, and Treatment of Methamphetamine Use Disorder: A Review

IMPORTANCE

The prevalence of and mortality associated with methamphetamine use has doubled during the past 10 years. There is evidence suggesting that methamphetamine use disorder could be the next substance use crisis in the United States and possibly worldwide.

OBSERVATION

The neurobiology of methamphetamine use disorder extends beyond the acute effect of the drug as a monoaminergic modulator and includes intracellular pathways focused on oxidative stress, neurotoxic and excitotoxic effects, and neuroinflammation. Similarly, the clinical picture extends beyond the acute psychostimulatory symptoms to include complex cardiovascular and cerebrovascular signs and symptoms that need to be identified by the clinician. Although there are no pharmacologic treatments for methamphetamine use disorder, cognitive behavioral therapy, behavioral activation, and contingency management show modest effectiveness.

CONCLUSIONS AND RELEVANCE

There is a need to better understand the complex neurobiology of methamphetamine use disorder and to develop interventions aimed at novel biological targets. Parsing the disorder into different processes (eg, craving or mood-associated alterations) and targeting the neural systems and biological pathways underlying these processes may lead to greater success in identifying disease-modifying interventions. Finally, mental health professionals need to be trained in recognizing early cardiovascular and cerebrovascular warning signs to mitigate the mortality associated with methamphetamine use disorder.

Non-pharmacological interventions for methamphetamine use disorder: a systematic review

BACKGROUND

Methamphetamine (METH) use is on the rise globally, with the number of treatment seekers increasing exponentially across the globe. Evidence-based therapies are needed to meet rising treatment needs. This systematic review intends to appraise the existing evidence to identify effective non-pharmaceutical approaches for the treatment of METH use disorder.

METHODS

Five electronic bibliographic databases-Ovid (Medline), Embase, Cumulative Index of Nursing and Allied Health Literature (CINAHL), Web of Science and PsycINFO- were searched to identify relevant studies that were published between January 1995 to February 2020. Studies were selected and assessed by two independent reviewers. A systematic review of data from both randomised control trials (RCT) and non-RCTs was conducted to appraise the evidence.

RESULTS

A total of 44 studies were included in the review. Behavioural interventions, i.e. cognitive behavioural therapy (CBT), contingency management (CM), exercise, residential rehabilitation based therapies, repetitive transcranial magnetic stimulation (rTMS), and matrix model demonstrated treatment efficacy in promoting abstinence, reducing methamphetamine use or craving in the participants. While CM interventions showed the strongest evidence favouring the outcomes assessed, tailored CBT alone or with CM was also effective in the target population.

CONCLUSIONS

Behavioural interventions should be considered as the first line of treatment for methamphetamine use disorder. Future studies should address the longevity of the effects, and limitations due to smaller sample sizes and high dropout rates to enable better assessment of evidence.

Stereoselective Steady-State Disposition and Bioequivalence of Brand and Generic Bupropion in Adults

The antidepressant bupropion is stereoselectively metabolized and metabolite enantiomers have differential pharmacologic effects, but steady-state enantiomeric disposition is unknown. Controversy persists about bupropion XL 300 mg generic equivalence to brand product, and whether generics might have different stereoselective disposition leading to enantiomeric non-bioequivalence and, thus, clinical nonequivalence. This preplanned follow-on analysis of a prospective, randomized, double-blinded, crossover study of brand and 3 generic bupropion XL 300 mg products measured steady-state enantiomeric plasma and urine parent bupropion and primary and secondary metabolite concentrations and evaluated bioequivalence and pharmacokinetics. Steady-state plasma and urine bupropion disposition was markedly stereoselective, with up to 40-fold differences in plasma concentrations of the active metabolite S,S-hydroxybupropion vs. R,R,-hydroxybupropion. Urine metabolite glucuronides were prominent, but glucuronidation was metabolite-specific and enantioselective. There were no differences between any generic and brand, or between generics, in plasma enantiomer concentrations of bupropion or the major metabolites. All generic products satisfied formal bioequivalence criteria (peak plasma concentration (C_max ) and area under the plasma concentration-time curve over 24 hours (AUC_0-24 )) using enantiomers for bupropion as well as for metabolites, and generics were comparable to each other, and were considered bioequivalent, based on enantiomeric analysis. Enantiomeric bioequivalence explains the previously observed therapeutic equivalence of bupropion generics and brand in treating major depression. These results have important implications for understanding the clinical therapeutic effects of bupropion based on complex and stereoselective metabolism.

Amphetamine/Dextroamphetamine Salts for Delayed Orgasm and Anorgasmia in Men: A Pilot Study

OBJECTIVE

To describe our experience with amphetamine/dextroamphetamine salts (AMP) as a treatment for delayed orgasm/anorgasmia (DO/AO).

METHODS

We identified patients with DO/AO from September 2017 to September 2019. Baseline characteristics and patient-reported orgasmic latency time (OLT) were recorded. After extensive screening, patients were treated with AMP. Validated questionnaires were administered including International Index of Erectile Function, quantitative Androgen Deficiency in the Aging Male and Adult ADHD Self-Report Scale. OLT change, adverse effects, and patient satisfaction were assessed. Baseline characteristics were compared using chi-squared test. OLT changes were compared with one-way ANOVA. Multivariable logistic regression was performed to identify predictors of treatment success. P < 0.05 was statistically significant.

RESULTS

Seventeen men received AMP - 6 of 17 (35.3%) for AO and 11 of 17 (64.7%) for DO, with median follow-up 1.0 year (interquartile range [IQR] 1.0 year). Amongst responders, AMP improved subjective experience of sex in 8 of 17 (47.1%) patients (2/6 with AO). Of those, 6 of 17 (35.3%; 1/6 with AO) experienced reduced OLT or increased frequency of orgasm. Non-responders were older than responders, with median age 69.5 (IQR 4.3) vs 61.0 years (IQR 12.3; P = 0.024). There were no other significant differences in baseline characteristics among responders. Of note, 6 of 8 (75%) responders and 8 of 9 (88.9%) non-responders failed other treatment modalities prior to AMP. Among responders with DO and improved OLT, mean OLT decreased by 72.3% (40.7 to 11.1 minutes, P = 0.049) during intercourse. Minimal side effects were noted including insomnia and jitters, each in one patient respectively.

CONCLUSION

AMP as a treatment for AO/DO merits further investigation. Measurable improvements in OLT or frequency of orgasm occurred in more than a third of patients. Larger prospective multicenter studies with strict inclusion and exclusion criteria are warranted.

Stereoselective Bupropion Hydroxylation by Cytochrome P450 CYP2B6 and Cytochrome P450 Oxidoreductase Genetic Variants

Bioactivation of the antidepressant and smoking cessation drug bupropion is catalyzed predominantly by CYP2B6. The metabolite hydroxybupropion derived from t-butylhydroxylation is considered to contribute to the antidepressant and smoking-cessation effects of the parent drug. Bupropion hydroxylation is the canonical in vitro and in vivo probe for CYP2B6 activity. P450 also requires obligate partnership with P450 oxidoreductase (POR). Human CYP2B6 and POR genes are highly polymorphic. Some CYP2B6 variants affect bupropion disposition. This investigation evaluated the influence of several human CYP2B6 and POR genetic variants on stereoselective bupropion metabolism, using an insect cell coexpression system containing CYP2B6, POR, and cytochrome b ₅ Based on intrinsic clearances (Cl_ints), relative activities for S,S-hydroxybupropion formation were in the order CYP2B6.4 > CYP2B6.1 > CYP2B6.17 > CYP2B6.5 > CYP2B6.6 ≈ CYP2B6.26 ≈ CYP2B6.19 > CYP2B6.7 > CYP2B6.9 > > CYP2B6.16 and CYP2B6.18; relative activities for R,R-hydroxybupropion formation were in the order CYP2B6.17 > CYP2B6.4 > CYP2B6.1 > CYP2B6.5 ≈ CYP2B6.19 ≈ CYP2B6.26 > CYP2B6.6 > CYP2B6.7 ≈ CYP2B6.9 > > CYP2B6.16 and CYP2B6.18. Bupropion hydroxylation was not influenced by POR variants. CYP2B6-catalyzed bupropion hydroxylation is stereoselective. Though V_max and K_m varied widely among CYP2B6 variants, stereoselectivity was preserved, reflected by similar Cl_int(S,S-hydroxybupropion)/Cl_int(R,R-hydroxybupropion) ratios (1.8-2.9), except CYP2B6.17, which was less enantioselective. Established concordance between human bupropion hydroxylation in vitro and in vivo, together with these new results, suggests additional CYP2B6 variants may influence human bupropion disposition. SIGNIFICANCE STATEMENT: Bupropion pharmacokinetics, metabolism, and clinical effects are affected by the CYP2B6*6 polymorphism. Other expressed CYP2B6 polymorphisms had diminished (*5, *6, *7, *9, *19, *26) or defective (*16, *18) in vitro bupropion hydroxylation. P450 oxidoreductase genetic variants had no effect on metabolism, suggesting no clinical consequence of this polymorphism. These CYP2B6 polymorphisms may portend diminished in vivo bupropion hydroxylation and predict additional clinically important variant alleles.

Methamphetamine Use: A New Wave in the Opioid Crisis?

BACKGROUND

The ongoing drug crisis in the United States continues to be headlined with numbers of deaths related to opioid overdose. Less known to the public and health care providers is the rise in methamphetamine use, often in conjunction with opioids or adulterated with fentanyl. An old practice with a new twist is the use of methamphetamine in conjunction with an opioid such as heroin.

PURPOSE

Although there are no Food and Drug Administration-approved medications to treat individuals with stimulant use disorders, a review of available studies suggests a few promising medications that may be helpful for patients in early recovery from methamphetamine.

OUTCOME

Some individuals are more likely to respond to medications such as long-acting naltrexone, bupropion, and mirtazapine, who have light-to-moderate use of methamphetamine. Naloxone kits should be considered for all patients who are actively using stimulants because of a high potential of adulterated methamphetamine.

Hospitalization outcomes of people who use drugs: One size does not fit all

People with opioid use disorder (OUD) have worse hospital outcomes and higher healthcare costs. There are rising reports of people with OUD also using other classes of drugs, however patterns of substance use have not been evaluated for differential effects on hospital outcomes. We performed a data-analysis of the Healthcare Utilization Project's National Readmissions Database, examining the effects of patterns of substance use, age, gender, and diagnosis on the outcomes of Against Medical Advice (AMA) discharges and 30-day readmissions. About one-third of the patients with OUD who were admitted to the hospital had at least one additional substance use disorder (SUD). Thirteen percent of persons with OUD were discharged AMA, and 12% were readmitted to the hospital within 30 days of discharge. Compared to people with OUD alone, people who used stimulants had increased odds of AMA discharge (aOR 1.83 (CI 1.73, 1.96)) and 30-day readmission (aOR 1.30 (95% CI 1.23, 1.37)). Multiple concomitant substance use disorders were associated with increased odds of AMA discharge and 30-day readmission. Conclusions: People with OUD have high rates of both AMA discharges and 30 day-readmissions, and there is a layered effect of increasing co-occurring SUDs leading to worse hospitalization outcomes. The heterogeneity of drug use patterns needs to be considered when developing strategies to improve health care outcomes for people with substance use disorder.

Randomized, Placebo-Controlled Trial of Targeting Neuroinflammation with Ibudilast to Treat Methamphetamine Use Disorder

Methamphetamine (MA) triggers neuroinflammation and medications that counteract MA-induced neuroinflammation may reduce MA-induced neurodegeneration and improve neurocognition and treatment outcomes in MA use disorder. We performed a randomized, placebo-controlled trial to determine the safety and efficacy of ibudilast (IBUD), a phosphodiesterase inhibitor that reduces neuroinflammation, for the treatment of MA use disorder. Treatment-seeking volunteers with MA use disorder were randomly assigned to receive 12 weeks of IBUD 50 mg twice daily (N = 64) or placebo (N = 61) with medication management counseling. Participants visited the outpatient research clinic twice weekly to provide urine specimens for drug screens and undergo study assessments. The primary outcome was end of treatment MA-abstinence (EOTA) during weeks 11 and 12 of treatment. Serum IBUID levels were measured for IBUD participants during week 3 of treatment. There was no difference in EOTA for IBUD (14%) versus placebo (16%, p > 0.05). There was no correlation between serum IBUD levels and MA use during treatment and mean IBUD levels for participants with (mean = 51.3, SD = 20.3) and without (mean = 54.7, SD = 33.0, p = 0.70) EOTA. IBUD was well tolerated. IBUD did not facilitate MA abstinence in this outpatient trial. Whether targeting neuroinflammation, either with IBUD in other subgroups of MA users or clinical trial designs, or with other anti-inflammatory medications, is an effective strategy for treating MA use disorder is not clear. Graphical Abstract The proportion of urine drug screens negative for methamphetamine (MA) during the two week lead-in period (weeks -2 and - 1) and the 12 week medication treatment period (weeks 1-12) for ibudilast versus placebo.

Pharmacotherapeutic strategies for methamphetamine use disorder: mind the subgroups

Introduction: Drug use related deaths are increasing and the lack of effective treatment for psychostimulants can be largely held responsible. Particularly, no pharmacotherapy is approved for methamphetamine (METH) use disorder despite decades of research. Only psychosocial interventions are clinically used, with limited long-term recovery and relapse.Areas covered: This review aims to select and describe the most relevant findings to date. Selected clinical trials were found in PubMed using the following keywords ('methamphetamine') and ('addiction' OR 'withdrawal' OR 'treatment' OR 'pharmacotherapy'). Randomized placebo-controlled trials enrolling treatment-seeking METH-dependent subjects and inherent secondary analysis were included.Expert opinion: Overall, end-of-treatment abstinence, reduced METH use or lower relapse rates were seen on METH dependent subgroups or attained significance only following post hoc analysis, irrespective of the medication tested. For example, light and heavy METH users seem to respond differently to pharmacotherapy. This together with the heterogeneous nature of the METH dependent population strongly suggests that some drugs herein described (e.g. mirtazapine, methylphenidate) should be further tested in clinical trials focused on subgroups. Lastly, objective measures, such as urinalysis, are mandatory to include in clinical trials and early treatment response and/or medication compliance should be carefully monitored and considered as predictors of success/failure.

Psychological treatment for methamphetamine use and associated psychiatric symptom outcomes: A systematic review

BACKGROUND

Regular methamphetamine use is associated with increased rates of psychiatric symptoms. Although there has been a substantial body of research reporting on the effectiveness of psychological treatments for reducing methamphetamine use, there is a paucity of research examining the effects of these treatments on co-occurring psychiatric symptoms. We addressed this gap by undertaking a systematic review of the evidence of the effectiveness of psychological treatments for methamphetamine use on psychiatric symptom outcomes in randomized controlled trials.

METHODS

A narrative synthesis of studies was conducted following the Cochrane Handbook for Systematic Reviews of Interventions and the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) statement to inform methodology. Eight electronic peer-reviewed databases were searched. Ten eligible studies were assessed.

RESULTS

Most studies found an overall reduction in levels of methamphetamine use and psychiatric symptoms among samples as a whole. Although brief interventions were effective, there is evidence that more intensive interventions have greater impact on methamphetamine use and/or psychiatric symptomatology. Intervention attendance was variable.

CONCLUSIONS

The evidence suggests that a variety of psychological treatments are effective in reducing levels of methamphetamine use and improving psychiatric symptoms. Future research should consider how psychological treatments could maximize outcomes in the co-occurring domains of methamphetamine use and psychiatric symptoms, with increasing treatment attendance as a focus. PROSPERO registration number: CRD42016043657.

Methamphetamine use drives decreases in viral suppression for people living with HIV released from a large municipal jail: Results of the LINK LA clinical trial

BACKGROUND

People living with HIV (PLWH) often experience decreases in HIV viral suppression (VS) after release from jail. The Linking Inmates to Care in LA (LINK LA) peer navigation intervention helped maintain VS 12 months after release from jail compared to standard of care. In this study, we analyzed correlates of substance use and tested whether substance use was an independent correlate of decreased VS in LINK LA participants.

METHODS

We analyzed LINK LA data collected at baseline, 3, and 12 months. We defined high-risk drug use as any reported methamphetamine, cocaine, or opioid use in the 30 days prior to a study visit (or jail entry at baseline). We used generalized linear mixed models to test associations of sociodemographic variables with type of substance used, and we tested correlates of VS while controlling for time, the intervention, and their interaction.

RESULTS

At baseline (n = 356), 71% of participants reported high-risk drug use: 58%, methamphetamine; 17%, cocaine; 7%, heroin; and 4%, prescription opioids. Non-Hispanic Whites and those younger than 35 were most likely to use methamphetamine; Blacks were most likely to use cocaine; people who inject drugs were most likely to use opioids. Participants who used high-risk drugs had 53% lower adjusted odds than non-users of maintaining VS (AOR 0.47, 95% CI 0.31-0.70, p < 0.001).

CONCLUSION

High-risk drug use, dominated by methamphetamine use, independently correlated with decreased VS among recently incarcerated PLWH. Improving HIV care continuum outcomes among populations leaving jail requires attention to efforts to address high-risk drug use.

Social identity differentiation predicts commitment to sobriety and wellbeing in residents of therapeutic communities

RATIONALE

Therapeutic communities (TC) for alcohol and other drug treatment rely strongly on social factors as agents of recovery; an approach known as 'community-as-method'. This study adopted a social identity approach in examining the relative strength of participants' recovery group identity and substance using group identity at admission (T1) and after six months (T2) in a TC.

OBJECTIVES

Were to investigate whether identity differentiation - the extent to which respondents see themselves more as belonging to recovery groups than belonging to substance using groups - (a) is related to individuals' primary substance of concern (i.e., amphetamine type stimulants; alcohol; other drugs), and (b) predicts positive indicators of recovery six months after entering a therapeutic community.

METHOD

Adults (N = 307) entering one of five Australian therapeutic communities (TC) completed measures of identification (user, recovery), commitment to sobriety, psychological distress, and personal wellbeing.

RESULTS

Participants' endorsement of the user and recovery identity at T1 and T2 did not differ as a function of primary substance of concern. User identity diminished over the six months while recovery identity remained high, regardless of primary drug category. Identity differentiation measured at T2 accounted for 20-25% variance in commitment to sobriety and wellbeing, after accounting for participant demographics, addiction severity, and T1 identity variables.

CONCLUSIONS

These findings highlight the importance of the relative strength of recovery over substance use related identities in supporting recovery indicators and the central role of the TC in supporting this trajectory.

The Use of Naltrexone in Dermatology. Current Evidence and Future Directions

Naltrexone is a competitive opioid receptor antagonist approved as supportive treatment in alcohol dependence and opioid addiction. At a dose of 50-100 mg daily, naltrexone is used off-label in dermatology for the treatment of trichotillomania and different types of pruritus. At a dose as low as 1- 5 mg per day, naltrexone demonstrates immunomodulatory action i.e. modulates Toll-like receptors signaling, decreases release of proinflammatory cytokines (tumor necrosis factor, interleukin-6, interleukin- 12), inhibits T lymphocyte proliferation, down-regulates the expression of chemokine receptors and adhesion molecules. The efficacy of standard and low doses of naltrexone in a variety of dermatological disorders has been reported. These include diseases such as familial benign chronic pemphigus (Hailey-Hailey disease), dermatomyositis, systemic sclerosis, psoriasis and lichen planopilaris. Optimistic preliminary findings, low cost of therapy and good tolerance make naltrexone a promising alternative therapy or adjunct drug in dermatology.

Impact of Substance Use Disorder Pharmacotherapy on Executive Function: A Narrative Review

Substance use disorders are chronic, relapsing, and harmful conditions characterized by executive dysfunction. While there are currently no approved pharmacotherapy options for stimulant and cannabis use disorders, there are several evidence-based options available to help reduce symptoms during detoxification and aid long-term cessation for those with tobacco, alcohol and opioid use disorders. While these medication options have shown clinical efficacy, less is known regarding their potential to enhance executive function. This narrative review aims to provide a brief overview of research that has investigated whether commonly used pharmacotherapies for these substance use disorders (nicotine, bupropion, varenicline, disulfiram, acamprosate, nalmefene, naltrexone, methadone, buprenorphine, and lofexidine) effect three core executive function components (working memory, inhibitory control and cognitive flexibility). While pharmacotherapy-induced enhancement of executive function may improve cessation outcomes in dependent populations, there are limited and inconsistent findings regarding the effects of these medications on executive function. We discuss possible reasons for the mixed findings and suggest some future avenues of work that may enhance the understanding of addiction pharmacotherapy and cognitive training interventions and lead to improved patient outcomes.

Molecular Mechanisms of Amphetamines

There is a plethora of amphetamine derivatives exerting stimulant, euphoric, anti-fatigue, and hallucinogenic effects; all structural properties allowing these effects are contained within the amphetamine structure. In the first part of this review, the interaction of amphetamine with the dopamine transporter (DAT), crucially involved in its behavioral effects, is covered, as well as the role of dopamine synthesis, the vesicular monoamine transporter VMAT2, and organic cation 3 transporter (OCT3). The second part deals with requirements in amphetamine's effect on the kinases PKC, CaMKII, and ERK, whereas the third part focuses on where we are in developing anti-amphetamine therapeutics. Thus, treatments are discussed that target DAT, VMAT2, PKC, CaMKII, and OCT3. As is generally true for the development of therapeutics for substance use disorder, there are multiple preclinically promising specific compounds against (meth)amphetamine, for which further development and clinical trials are badly needed.