Treatment of Adolescent Cannabis Use Disorders

This review summarizes treatments for cannabis use disorder (CUD) in adolescents. The best supported CUD treatments are cognitive behavioral psychotherapies, including family-based models that facilitate environmental changes and youth-focused models that incorporate skills training, motivational interviewing, and contingency management to promote reductions in cannabis use. Some medications show promise in reducing cannabis craving and withdrawal symptoms. Further research is needed on the efficacy and implementation of existing treatments given the changes in cannabis use trends over time and on emerging technologies that may expand access to evidence-based CUD treatments.

Program Evaluation to Aid Choice of Aripiprazole or Risperidone for Hospitalized Adolescents with Cannabis Use Disorder and Psychosis

Introduction: Co-occurring cannabis use and psychosis is an increasing problem. No single behavioral or pharmacologic treatment has emerged as clearly superior. To address the gap, this nonrandomized, quality improvement project compares outcomes for adolescents with co-occurring cannabis use disorder and psychosis prescribed risperidone or aripiprazole. Materials and Methods: This project is a retrospective chart review of 110 adolescents (ages 13-21 years) hospitalized for psychosis and co-occurring cannabis use disorder. The primary outcomes are length of stay and length of stay index. Results: Adolescents prescribed risperidone compared with aripiprazole had a significantly greater length of stay (9.7 days vs. 5.8 days, p = 0.002) and length of stay index (1.4 vs. 0.79, p = 0.004). Conclusions: Adolescents hospitalized for co-occurring psychosis and cannabis use disorder had a significantly longer length of stay and length of stay index. These data are consistent with a more rapid reduction in acute psychotic symptoms for aripiprazole compared with risperidone in the context of co-occurring cannabis use disorder.

Unravelling the landscape of Cannabis craving pharmacological treatments: a PRISMA-guided review of evidence

Currently, few treatments are available for craving in general, and none of them have received approval for cannabis craving. The objective of this review is to evaluate existing studies analysing treatments for cannabis craving and explore novel treatment possibilities for these patients. The study followed PRISMA guidelines and conducted an extensive database search. Inclusion criteria included human randomised controlled trials examining drug effects on craving symptoms. Exclusion criteria involved studies unrelated to craving, non-pharmacological treatments, duplicates, and non-English/Spanish/Portuguese articles. Our included 22 studies that investigated a wide range of compounds used for cravings related to other drugs, as well as interventions based on healthcare professionals' empirical knowledge. The current pharmacological treatments largely involve off-label drug use and the utilisation of cannabinoid-based medications, such as combinations of THC and lofexidine, oxytocin, progesterone, and N-acetylcysteine. These emerging treatments show promise and have the potential to revolutionise current clinical practices, but further investigation is needed to establish their efficacy. In this context, it is essential to consider non-pharmacological interventions, such as psychotherapy and behavioural treatments. These approaches play a crucial role in complementing pharmacological interventions and addressing the complex nature of the disorder.

An analysis of cannabinoid hyperemesis syndrome Reddit posts and themes

INTRODUCTION

Reddit hosts a large active community of members dedicated to the discussion of cannabinoid hyperemesis syndrome. We sought to describe common themes discussed and the most frequently mentioned triggers and therapies for cannabinoid hyperemesis syndrome exacerbations in the Reddit online community.

METHODS

Data collected from six subreddits were filtered using natural language processing to curate posts referencing cannabinoid hyperemesis syndrome. Based on a manual review of posts, common themes were identified. A machine learning model was trained using the manually categorized data to automatically classify the themes for the rest of the posts so that their distributions could be quantified.

RESULTS

From August 2018 to November 2022, 2683 unique posts were collected. Thematic analysis resulted in five overall themes: cannabinoid hyperemesis syndrome-related science; symptom timing; cannabinoid hyperemesis syndrome treatment and prevention; cannabinoid hyperemesis syndrome diagnosis and education; and health impacts. Additionally, 447 trigger and 664 therapy-related posts were identified. The most commonly mentioned triggers for cannabinoid hyperemesis syndrome episodes included: food and drink (n = 62), cannabinoids (n = 45), mental health (e.g., stress, anxiety) (n = 27), and alcohol (n = 22). Most commonly mentioned cannabinoid hyperemesis syndrome therapies included: hot water/bathing (n = 62), hydration (n = 60), antiemetics (n = 42), food and drink (n = 38), gastrointestinal medications (n = 38), behavioral therapies (e.g., meditation, yoga) (n = 35), and capsaicin (n = 29).

DISCUSSION

Reddit posts for cannabinoid hyperemesis syndrome provide a valuable source of community discussion and individual reports of people experiencing cannabinoid hyperemesis syndrome. Mental health and alcohol were frequently reported triggers within the posts but are not often identified in the literature. While many of the therapies mentioned are well documented, behavioral responses such as meditation and yoga have not been explored by the scientific literature.

CONCLUSIONS

Knowledge shared via online social media platforms contains detailed information on self-reported cannabinoid hyperemesis syndrome disease and management experiences, which could serve as valuable data for the development of treatment strategies. Further longitudinal studies in patients with cannabinoid hyperemesis syndrome are needed to corroborate these findings.

Influence of pregabalin maintenance on cannabis effects and related behaviors in daily cannabis users

No medications are approved for cannabis use disorder (CUD), though a small clinical trial demonstrated that the voltage-dependent calcium channel (VDCC) ligand gabapentin reduced cannabis use in treatment seekers. VDCCs are modulated by cannabinoid (CB) ligands, and there are shared effects between CB agonists and VDCC ligands. This overlapping neuropharmacology and the initial clinical results supported the evaluation of pregabalin, a "next-generation" VDCC ligand, as a CUD medication. Two separate placebo-controlled, double-blind, counterbalanced, within-subjects human laboratory studies tested placebo and 300 (N = 2 females, 11 males; Experiment [EXP] 1) or 450 (N = 3 females, 11 males; EXP 2) mg/day pregabalin in cannabis users who were not seeking treatment or trying to reduce/quit their cannabis use. The protocol consisted of two outpatient maintenance phases (11 days in EXP 1 and 15 days in EXP 2) that concluded with four experimental sessions within each phase. During experimental sessions, maintenance continued, and participants completed two 2-day blocks of sampling and self-administration sessions to determine the reinforcing effects of smoked cannabis (0% and 5.9% delta⁹-tetrahydrocannabinol [THC]), as well as subjective, attentional bias, performance, and physiological responses. In addition, naturalistic cannabis use, side effects, sleep quality, craving, and other self-reported substance use were measured during pregabalin maintenance. Cannabis was self-administered and produced prototypical effects, but pregabalin generally did not impact the effects of cannabis or alter naturalistic use. These human laboratory results in cannabis users not trying to reduce/quit their use do not support the efficacy of pregabalin as a stand-alone pharmacotherapy for CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Results from a randomized, double-blind, placebo-controlled, crossover, multimodal-MRI pilot study of gabapentin for co-occurring bipolar and cannabis use disorders

Disrupted brain gamma-aminobutyric acid (GABA)/glutamate homeostasis is a promising target for pharmacological intervention in co-occurring bipolar disorder (BD) and cannabis use disorder (CUD). Gabapentin is a safe and well-tolerated medication, FDA-approved to treat other neurological diseases, that restores GABA/glutamate homeostasis, with treatment studies supporting efficacy in treating CUD, as well as anxiety and sleep disorders that are common to both BD and CUD. The present manuscript represents the primary report of a randomized, double-blind, placebo-controlled, crossover (1-week/condition), multimodal-MRI (proton-MR spectroscopy, functional MRI) pilot study of gabapentin (1200 mg/day) in BD + CUD (n = 22). Primary analyses revealed that (1) gabapentin was well tolerated and adherence and retention were high, (2) gabapentin increased dorsal anterior cingulate cortex (dACC) and right basal ganglia (rBG) glutamate levels and (3) gabapentin increased activation to visual cannabis cues in the posterior midcingulate cortex (pMCC, a region involved in response inhibition to rewarding stimuli). Exploratory evaluation of clinical outcomes further found that in participants taking gabapentin versus placebo, (1) elevations of dACC GABA levels were associated with lower manic/mixed and depressive symptoms and (2) elevations of rBG glutamate levels and pMCC activation to cannabis cues were associated with lower cannabis use. Though promising, the findings from this study should be interpreted with caution due to observed randomization order effects on dACC glutamate levels and identification of statistical moderators that differed by randomization order (i.e. cigarette-smoking status on rBG glutamate levels and pMCC cue activation). Nonetheless, they provide the necessary foundation for a more robustly designed (urn-randomized, parallel-group) future study of adjuvant gabapentin for BD + CUD.

Treatment of Cannabinoid Hyperemesis With Olanzapine: A Case Series

The use and availability of cannabis for recreational and medical purposes has become more widespread with increased legalization. Adverse health outcomes of this increased use include cannabinoid hyperemesis syndrome (CHS), which is underrecognized in medical settings. Cessation of substance use is the recommendation of choice for the complete resolution of CHS. However, interventions that provide rapid relief may be necessary in treatment-refractory cases. Little evidence is available to guide care in these cases. Here we report 4 cases of treatment-refractory CHS, all of which remitted after treatment with olanzapine. Olanzapine is known to block multiple neurotransmitter receptors involved in nausea and vomiting in chemotherapy-induced nausea and vomiting. Outcomes of the cases reported here suggest that off-label use of olanzapine may be effective in the symptomatic treatment of refractory CHS and may be the preferred treatment in cases in which comorbid psychotic symptoms or agitation are present.

[Cannabinoid hyperemesis syndromecan be relieved by hot showers]

This is a case report of a 19-year-old woman with cannabinoid hyperemesis syndrome (CHS), which is characterised by cyclic vomiting and nausea, relieved by hot showers and caused by chronic cannabis usage. Many diagnoses must be ruled out, but the suspicion of cannabis usage must be present. Early suspicion of CHS can prevent overtreatment and unnecessary investigations. Lack of evidence makes treatment difficult and is primarily symptomatic. Attention to cannabis usage is needed when admitting patients with emesis.

[Nabiximols as a substitute for cannabis]

Cannabis addiction is worldwide one of the most prevalent addictions, without any effective pharmacotherapeutic options. Nabiximols spray, consisting of 2.7 mg tetrahydrocannabinol (THC) and 2.5 mg cannabidiol (CBD), could serve as an effective substitution therapy for cannabis addiction. Researchers reported that patients who were treated for 12 weeks with nabiximols significantly reduced the number of days on which they used cannabis (18.6 days less compared to placebo users; 95% CI: 3.5-33.7). There was no difference between groups regarding general health, the use of other substances, cannabis craving, withdrawal symptoms or achieving abstinence.

The impact of naturalistic cannabis use on self-reported opioid withdrawal

OBJECTIVES

Four states have legalized medical cannabis for the purpose of treating opioid use disorder. It is unclear whether cannabinoids improve or exacerbate opioid withdrawal. A more thorough examination of cannabis and its impact on specific symptoms of opioid withdrawal is warranted.

METHOD

Two hundred individuals recruited through Amazon Mechanical Turk with past month opioid and cannabis use and experience of opioid withdrawal completed the survey. Participants indicated which opioid withdrawal symptoms improved or worsened with cannabis use and indicated the severity of their opioid withdrawal on days with and without cannabis.

RESULTS

62.5% (n = 125) of 200 participants had used cannabis to treat withdrawal. Participants most frequently indicated that cannabis improved: anxiety, tremors, and trouble sleeping. A minority of participants (6.0%, n = 12) indicated cannabis worsened opioid withdrawal, specifically symptoms of yawning, teary eyes, and runny nose. Across all symptoms, more participants indicated that symptoms improved with cannabis compared to those that indicated symptoms worsened with cannabis. Women reported greater relief from withdrawal with cannabis use than men.

DISCUSSION

These results show that cannabis may improve opioid withdrawal symptoms and that the size of the effect is clinically meaningful. It is important to note that symptoms are exacerbated with cannabis in only a minority of individuals. Prospectively designed studies examining the impact of cannabis and cannabinoids on opioid withdrawal are warranted.

Sex- and Gender-Based Analysis in Cannabis Treatment Outcomes: A Systematic Review

There is evidence that sex- and gender-related factors are involved in cannabis patterns of use, health effects and biological mechanisms. Women and men report different cannabis use disorder (CUD) symptoms, with women reporting worse withdrawal symptoms than men. The objective of this systematic review was to examine the effectiveness of cannabis pharmacological interventions for women and men and the uptake of sex- and gender-based analysis in the included studies. Two reviewers performed the full-paper screening, and data was extracted by one researcher. The search yielded 6098 unique records—of which, 68 were full-paper screened. Four articles met the eligibility criteria for inclusion. From the randomized clinical studies of pharmacological interventions, few studies report sex-disaggregated outcomes for women and men. Despite emergent evidence showing the influence of sex and gender factors in cannabis research, sex-disaggregated outcomes in pharmacological interventions is lacking. Sex- and gender-based analysis is incipient in the included articles. Future research should explore more comprehensive inclusion of sex- and gender-related aspects in pharmacological treatments for CUD.

Pharmacotherapies for Cannabis Use Disorders: Clinical Challenges and Promising Therapeutic Agents

This chapter reviews pharmacotherapies that have been trialled for cannabis dependence, identifying those that warrant further research and those of little or uncertain value. A diverse range of medicines have been tested, representing a broad range of pharmacological strategies. These include tetrahydrocannabinol preparations, various types of antidepressant, anxiolytics, a glutamatergic modulator and the neuropeptide oxytocin. Cannabinoid agonists warrant further research. For the FAAH inhibitor PF-04457845, oxytocin, varenicline and gabapentin, although there is a signal to indicate further research is warranted, these medications do not yet have sufficient evidence to support clinical use, and larger, longer-term trials are needed in representative treatment-seeking populations. Special populations that warrant consideration are those with cannabis dependence and concurrent mental health conditions and those that develop dependence through therapeutic use.

Pharmacotherapies for cannabis dependence

BACKGROUND

Globally, cannabis use is prevalent and widespread. There are currently no pharmacotherapies approved for treatment of cannabis use disorders.This is an update of a Cochrane Review first published in the Cochrane Library in Issue 12, 2014.

OBJECTIVES

To assess the effectiveness and safety of pharmacotherapies as compared with each other, placebo or no pharmacotherapy (supportive care) for reducing symptoms of cannabis withdrawal and promoting cessation or reduction of cannabis use.

SEARCH METHODS

We updated our searches of the following databases to March 2018: the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, PsycINFO and Web of Science.

SELECTION CRITERIA

Randomised controlled trials (RCTs) and quasi-RCTs involving the use of medications to treat cannabis withdrawal or to promote cessation or reduction of cannabis use, or both, in comparison with other medications, placebo or no medication (supportive care) in people diagnosed as cannabis dependent or who were likely to be dependent.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by Cochrane.

MAIN RESULTS

We included 21 RCTs involving 1755 participants: 18 studies recruited adults (mean age 22 to 41 years); three studies targeted young people (mean age 20 years). Most (75%) participants were male. The studies were at low risk of performance, detection and selective outcome reporting bias. One study was at risk of selection bias, and three studies were at risk of attrition bias.All studies involved comparison of active medication and placebo. The medications were diverse, as were the outcomes reported, which limited the extent of analysis.Abstinence at end of treatment was no more likely with Δ⁹-tetrahydrocannabinol (THC) preparations than with placebo (risk ratio (RR) 0.98, 95% confidence interval (CI) 0.64 to 1.52; 305 participants; 3 studies; moderate-quality evidence). For selective serotonin reuptake inhibitor (SSRI) antidepressants, mixed action antidepressants, anticonvulsants and mood stabilisers, buspirone and N-acetylcysteine, there was no difference in the likelihood of abstinence at end of treatment compared to placebo (low- to very low-quality evidence).There was qualitative evidence of reduced intensity of withdrawal symptoms with THC preparations compared to placebo. For other pharmacotherapies, this outcome was either not examined, or no significant differences was reported.Adverse effects were no more likely with THC preparations (RR 1.02, 95% CI 0.89 to 1.17; 318 participants; 3 studies) or N-acetylcysteine (RR 0.94, 95% CI 0.71 to 1.23; 418 participants; 2 studies) compared to placebo (moderate-quality evidence). For SSRI antidepressants, mixed action antidepressants, buspirone and N-acetylcysteine, there was no difference in adverse effects compared to placebo (low- to very low-quality evidence).There was no difference in the likelihood of withdrawal from treatment due to adverse effects with THC preparations, SSRIs antidepressants, mixed action antidepressants, anticonvulsants and mood stabilisers, buspirone and N-acetylcysteine compared to placebo (low- to very low-quality evidence).There was no difference in the likelihood of treatment completion with THC preparations, SSRI antidepressants, mixed action antidepressants and buspirone compared to placebo (low- to very low-quality evidence) or with N-acetylcysteine compared to placebo (RR 1.06, 95% CI 0.93 to 1.21; 418 participants; 2 studies; moderate-quality evidence). Anticonvulsants and mood stabilisers appeared to reduce the likelihood of treatment completion (RR 0.66, 95% CI 0.47 to 0.92; 141 participants; 3 studies; low-quality evidence).Available evidence on gabapentin (anticonvulsant), oxytocin (neuropeptide) and atomoxetine was insufficient for estimates of effectiveness.

AUTHORS' CONCLUSIONS

There is incomplete evidence for all of the pharmacotherapies investigated, and for many outcomes the quality of the evidence was low or very low. Findings indicate that SSRI antidepressants, mixed action antidepressants, bupropion, buspirone and atomoxetine are probably of little value in the treatment of cannabis dependence. Given the limited evidence of efficacy, THC preparations should be considered still experimental, with some positive effects on withdrawal symptoms and craving. The evidence base for the anticonvulsant gabapentin, oxytocin, and N-acetylcysteine is weak, but these medications are also worth further investigation.

Systematic review of outcome domains and measures used in psychosocial and pharmacological treatment trials for cannabis use disorder

Cannabis use disorder (CUD) is prevalent and demand for treatment is increasing, yet few individuals engage in formal treatment and the efficacy of established interventions for CUD is modest. Existing clinical trials evaluating psychosocial and pharmacological treatments for CUD have incorporated a wide variety of measures for assessing cannabis use outcomes, including abstinence, self-reported frequency and quantity used, withdrawal, use/dependence severity, and other psychosocial outcomes. The heterogeneity of measures and outcomes has limited quantitative analyses of the comparative effectiveness of existing interventions. The purpose of this systematic review is to: 1) identify and characterize approaches for measuring cannabis use in existing CUD intervention trials, including abstinence, frequency and quantity of use, and 2) summarize measures used to assess treatment efficacy in other outcome domains (e.g., cannabis use severity, psychosocial functioning, cannabis withdrawal), and provide a platform for future research to evaluate which outcome measures are most likely to reflect treatment efficacy and clinically significant improvement in other outcome domains.

Tobacco use during cannabis cessation: Use patterns and impact on abstinence in a National Drug Abuse Treatment Clinical Trials Network study

BACKGROUND

It is common for cannabis users to also use tobacco. While data suggest that tobacco users have more difficulty achieving cannabis cessation, secondary analyses of clinical trial data sets may provide insight into the moderating variables contributing to this relationship, as well as changes in tobacco use during cannabis treatment. Those were the aims of this secondary analysis.

METHODS

The parent study was a multi-site trial of N-acetylcysteine for cannabis dependence conducted within the National Drug Abuse Treatment Clinical Trials Network. Participants were treatment-seeking adults (ages 18-50) who met criteria for cannabis dependence (N = 302). For cigarette smokers (n = 117), tobacco use was assessed via timeline follow-back and nicotine dependence was assessed via the Fagerström Test for Nicotine Dependence (FTND). Outcome measures included: 1) changes in tobacco use based on treatment assignment, nicotine dependence, and concurrent cannabis reduction/abstinence, and 2) independent associations between nicotine dependence and cannabis abstinence.

RESULTS

Cigarette smokers accounted for 39% of the sample (117/302), with a median FTND score of 3.0 (10-point scale). Among those with lower baseline nicotine dependence scores, cigarette smoking was reduced in the active treatment group compared to placebo. Those with moderate/high levels of nicotine dependence showed slight increases in smoking following active treatment. Nicotine dependence did not affect cannabis cessation.

CONCLUSIONS

Cigarette smoking during cannabis treatment was affected, but depended on baseline nicotine dependence severity, though dependence levels did not impact cannabis abstinence. Interventions that address both tobacco and cannabis are needed, especially due to an increasing prevalence of cannabis use.

When and How to Treat Possible Cannabis Use Disorder

Cannabis (marijuana) is a drug product derived from the plant Cannabis sativa. Cannabinoid is a general term for all chemical constituents of the cannabis plant. Legalization of marijuana in numerous US states, the availability of cannabis of higher potency, and the emergence of synthetic cannabinoids may have contributed to increased demand for related medical services. The most effective available treatments for cannabis use disorder are psychosocial approaches. There is no pharmacotherapy approved treatment. This article reviews the current state of knowledge regarding effective treatments for cannabis use disorder.

The effect of high-dose dronabinol (oral THC) maintenance on cannabis self-administration

BACKGROUND

There is a clear need for advancing the treatment of cannabis use disorders. Prior research has demonstrated that dronabinol (oral THC) can dose-dependently suppress cannabis withdrawal and reduce the acute effects of smoked cannabis. The present study was conducted to evaluate whether high-dose dronabinol could reduce cannabis self-administration among daily users.

METHODS

Non-treatment seeking daily cannabis users (N = 13) completed a residential within-subjects crossover study and were administered placebo, low-dose dronabinol (120 mg/day; 40 mg tid), or high-dose dronabinol (180-240 mg/day; 60-80 mg tid) for 12 consecutive days (order counterbalanced). During each 12-day dronabinol maintenance phase, participants were allowed to self-administer smoked cannabis containing <1% THC (placebo) or 5.7% THC (active) under forced-choice (drug vs. money) or progressive ratio conditions.

RESULTS

Participants self-administered significantly more active cannabis compared with placebo in all conditions. When active cannabis was available, self-administration was significantly reduced during periods of dronabinol maintenance compared with placebo maintenance. There was no difference in self-administration between the low- and high-dose dronabinol conditions.

CONCLUSIONS

Chronic dronabinol dosing can reduce cannabis self-administration in daily cannabis users and suppress withdrawal symptoms. Cannabinoid agonist medications should continue to be explored for therapeutic utility in the treatment of cannabis use disorders.

Randomised Controlled Trial (RCT) of cannabinoid replacement therapy (Nabiximols) for the management of treatment-resistant cannabis dependent patients: a study protocol

BACKGROUND

The cannabis extract nabiximols (Sativex®) effectively supresses withdrawal symptoms and cravings in treatment resistant cannabis dependent individuals, who have high relapse rates following conventional withdrawal treatments. This study examines the efficacy, safety and cost-effectiveness of longer-term nabiximols treatment for outpatient cannabis dependent patients who have not responded to previous conventional treatment approaches.

METHODS/DESIGN

A phase III multi-site outpatient, randomised, double-blinded, placebo controlled parallel design, comparing a 12-week course of nabiximols to placebo, with follow up at 24 weeks after enrolment. Four specialist drug and alcohol outpatient clinics in New South Wales, Australia. One hundred forty-two treatment seeking cannabis dependent adults, with no significant medical, psychiatric or other substance use disorders. Nabiximols is an oromucosal spray prescribed on a flexible dose regimen to a maximum daily dose of 32 sprays; 8 sprays (total 21.6 mg tetrahydrocannabinol (THC) and 20 mg cannabidiol (CBD)) four times a day, or matching placebo, dispensed weekly. All participants will receive six-sessions of individual cognitive behavioural therapy (CBT) and weekly clinical reviews. Primary endpoints are use of non-prescribed cannabis (self-reported cannabis use days, urine toxicology), safety measures (adverse events and abuse liability), and cost effectiveness (incremental cost effectiveness in achieving additional Quality Adjusted Life Years). Secondary outcomes include, improvement in physical and mental health parameters, substance use other than cannabis, cognitive functioning and patient satisfaction measures.

DISCUSSION

This is the first outpatient community-based randomised controlled study of nabiximols as an agonist replacement medication for treating cannabis dependence, targeting individuals who have not previously responded to conventional treatment approaches. The study and treatment design is modelled upon an earlier study with this population and more generally on other agonist replacement treatments (e.g. nicotine, opioids).

TRIAL REGISTRATION

Australian and New Zealand Clinical Trial Registry: ACTRN12616000103460 (Registered 1st February 2016).

Risk of neonatal and childhood morbidity among preterm infants exposed to marijuana

BACKGROUND

Limited data exist regarding the neonatal and neurodevelopmental outcomes of infants exposed to marijuana (MJ) in-utero, particularly among preterm infants. We hypothesized that MJ-exposed preterm infants would have worse neonatal and childhood developmental outcomes compared to MJ-unexposed infants.

METHODS

Secondary analysis of multicenter randomized-controlled trial of antenatal magnesium sulfate for the prevention of cerebral palsy was conducted. Singleton nonanomalous infants delivered <35 weeks exposed to MJ in-utero were compared to MJ-unexposed. Primary neonatal outcome was death, grade 3/4 intraventricular hemorrhage, periventricular leukomalacia, bronchopulmonary dysplasia, and/or stage II/III necrotizing enterocolitis before discharge. Primary childhood outcome was death, moderate/severe cerebral palsy, or/and Bayley II Scales <70 at age 2. Backward-stepwise regression used to estimate odds of primary outcomes.

RESULTS

1867 infants met inclusion criteria; 135(7.2%) were MJ-exposed. There were no differences in neonatal (20% vs. 26%, p = 0.14) or childhood (26% vs. 21%, p = 0.21) outcomes in MJ-exposed infants compared to MJ-unexposed infants. In adjusted models, MJ-exposure was not associated with adverse neonatal outcomes (aOR 0.83 95% CI 0.47,1.44) or early childhood outcomes (aOR 1.47, 95% CI 0.97,2.23).

CONCLUSIONS

Among infants born <35 weeks of gestation, MJ-exposure was not associated with adverse neonatal or childhood outcomes. Long-term follow-up studies are needed to assess later childhood neurodevelopmental outcomes following MJ-exposure.

The impact of cannabis use on patients enrolled in opioid agonist therapy in Ontario, Canada

Background

With the Canadian government legalizing cannabis in the year 2018, the potential harms to certain populations—including those with opioid use disorder—must be investigated. Cannabis is one of the most commonly used substances by patients who are engaged in medication-assisted treatment for opioid use disorder, the effects of which are largely unknown. In this study, we examine the impact of baseline and ongoing cannabis use, and whether these are impacted differentially by gender.

Methods

We conducted a retrospective cohort study using anonymized electronic medical records from 58 clinics offering opioid agonist therapy in Ontario, Canada. One-year treatment retention was the primary outcome of interest and was measured for patients who did and did not have a cannabis positive urine sample in their first month of treatment, and as a function of the proportion of cannabis-positive urine samples throughout treatment.

Results

Our cohort consisted of 644 patients, 328 of which were considered baseline cannabis users and 256 considered heavy users. Patients with baseline cannabis use and heavy cannabis use were at increased risk of dropout (38.9% and 48.1%, respectively). When evaluating these trends by gender, only female baseline users and male heavy users are at increased risk of premature dropout.

Interpretation

Both baseline and heavy cannabis use are predictive of decreased treatment retention, and differences do exist between genders. With cannabis being legalized in the near future, physicians should closely monitor cannabis-using patients and provide education surrounding the potential harms of using cannabis while receiving treatment for opioid use disorder.

Cannabis Epidemiology: A Selective Review

BACKGROUND

Globally, the most widely used set of compounds among the internationally regulated drugs is cannabis.

OBJECTIVE

To review evidence from epidemiological research on cannabis, organized in relation to this field's five main rubrics: quantity, location, causes, mechanisms, and prevention/ control.

METHOD

The review covers a selection of evidence from standardized population surveys, official statistics, and governmental reports, as well as published articles and books identified via MEDLINE, Web of Science, and Google Scholar as of July 2016.

RESULTS

In relation to quantity, an estimated 3% to 5% of the world population is thought to have tried a cannabis product, with at least one fairly recent use, mainly extra-medical and outside boundaries of prescribed use. Among cannabis users in the United States, roughly one in 7-8 has engaged in medical marijuana use. In relation to location, prevalence proportions reveal important variations across countries and between subgroups within countries. Regarding causes and mechanisms of starting to use cannabis, there is no compelling integrative and replicable conceptual model or theoretical formulation. Most studies of mechanisms have focused upon a 'gateway sequence' and person-to-person diffusion, with some recent work on disability-adjusted life years. A brief review of cannabis use consequences, as well as prevention and control strategies is also provided.

CONCLUSION

At present, we know much about the frequency and occurrence of cannabis use, with too little replicable definitive evidence with respect to the other main rubrics. Given a changing regulatory environment for cannabis products, new institutions such as an independent International Cannabis Products Safety Commission may be required to produce evidence required to weigh benefits versus costs. It is not clear that governmentsponsored research will be sufficient to meet consumer demand for balanced points of view and truly definitive evidence.

Gender differences in cannabis use disorder treatment: Change readiness and taking steps predict worse cannabis outcomes for women

INTRODUCTION

Gender differences in cannabis use and cannabis use disorder have been established. Regarding treatment, some evidence suggests that women are less responsive, though the mechanisms are not well understood. Motivation to change and self-efficacy are associated with better outcomes overall, and may help explain gender differences in cannabis use outcomes.

METHODS

A secondary data analysis of a double-blind placebo controlled trial of buspirone treatment for cannabis dependence (N=175) was conducted. Self-report assessments of motivation to change, self-efficacy, and other clinical correlates were completed at baseline, and cannabis use was measured throughout the study.

RESULTS

There was a significant interaction between gender and taking steps on abstinence. Counter to hypothesis, higher taking steps reduced likelihood of achieving abstinence among women; there was no association among men. Subsequently, taking steps was associated with self-efficacy and quantity of use among men, and cannabis related problems among women. There was a significant interaction between gender and readiness to change on creatinine adjusted cannabinoid levels. Change readiness was positively associated with cannabinoid levels among women, but not men.

CONCLUSIONS

Motivation to change and initiation of change behavior predict worse cannabis outcomes in women. Men and women differ in what motivates change behavior. Social desirability, neurobiology, and treatment type may impact these effects. Gender differences in cannabis use and treatment responsiveness must be considered in future studies.

Are Alcohol Anti-relapsing and Alcohol Withdrawal Drugs Useful in Cannabinoid Users?

Cannabinoids are still classified as illegal psychoactive drugs despite their broad and increasingly acknowledged therapeutic potential. These substances are most famous for their wide recreational use, particularly among young adults to either alter the state of consciousness, intensify pleasure induced by other psychoactive substances or as an alternative to the previously abused drugs. It is important to emphasize that cannabinoids are often taken together with a variety of medications intended for the treatment of alcohol use disorder (AUD) or alcohol withdrawal syndrome (AWS). These medications include disulfiram, acamprosate, and naltrexone. In this paper, we summarize recent advances in the knowledge of possible beneficial effects and interactions between cannabinoids and drugs commonly used for treatment of AUD and AWS either comorbid or existing as a separate disorder.

Effects of zolpidem alone and in combination with nabilone on cannabis withdrawal and a laboratory model of relapse in cannabis users

RATIONALE

Each year, over 300,000 individuals in the USA enter treatment for cannabis use disorder (CUD). The development of effective pharmacotherapy for CUD is a priority.

OBJECTIVE

This placebo-controlled study examined the effects of zolpidem alone and in combination with nabilone on cannabis withdrawal and a laboratory measure of relapse.

METHODS

Eleven daily, non-treatment-seeking cannabis users completed three, 8-day inpatient phases; each phase tested a different medication condition in counter-balanced order. On the first day of each phase, participants were administered placebo capsules t.i.d. and smoked experimenter-administered active cannabis (5.6 % Δ(9)-tetrahydrocannabinol (THC)). On days 2-8, the participants were administered capsules containing either placebo (0 mg at 0900, 1800, and 2300 hours), zolpidem (0 mg at 0900 and 1800, and 12.5 mg at 2300), or zolpidem (12.5 mg at 2300) and nabilone (3 mg at 0900 and 1800). Cannabis withdrawal, subjective capsule effects, and cognitive performance were examined on days 3-4, when only inactive cannabis (0.0 % THC) was available for self-administration. "Relapse" was measured on days 5-8, when participants could self-administer active cannabis.

RESULTS

Both medication conditions decreased withdrawal-related disruptions in sleep, but only zolpidem in combination with nabilone decreased withdrawal-related disruptions in mood and food intake relative to placebo. Zolpidem in combination with nabilone, but not zolpidem alone, decreased self-administration of active cannabis. Zolpidem in combination with nabilone also produced small increases in certain abuse-related subjective capsule ratings, while zolpidem alone did not. Neither medication condition altered cognitive performance.

CONCLUSIONS

Clinical testing of nabilone, either alone, or in combination with zolpidem is warranted.

Effects of fixed or self-titrated dosages of Sativex on cannabis withdrawal and cravings

BACKGROUND

There is currently no pharmacological treatment approved for cannabis dependence. In this proof of concept study, we assessed the feasibility/effects of fixed and self-titrated dosages of Sativex (1:1, Δ(9)-tetrahydrocannabinol (THC)/cannabidiol (CBD)) on craving and withdrawal from cannabis among nine community-recruited cannabis-dependent subjects.

METHODS

Participants underwent an 8-week double-blind placebo-controlled trial (an ABACADAE design), with four smoke as usual conditions (SAU) (A) separated by four cannabis abstinence conditions (B-E), with administration of either self-titrated/fixed doses of placebo or Sativex (up to 108 mg THC/100 mg CBD). The order of medication administration during abstinence conditions was randomized and counterbalanced. Withdrawal symptoms and craving were assessed using the Cannabis Withdrawal Scale (CWS), Marijuana Withdrawal Checklist (MWC) and Marijuana Craving Questionnaire (MCQ). Medication use was assessed during the study by means of self-reports, vial weight control, toxicology and metabolite analysis. Cannabis use was assessed by means of self-reports.

RESULTS

High fixed doses of Sativex were well tolerated and significantly reduced cannabis withdrawal during abstinence, but not craving, as compared to placebo. Self-titrated doses were lower and showed limited efficacy as compared to high fixed doses. Participants reported a significantly lower "high" following Sativex or placebo as compared to SAU conditions. Cannabis/medication use along the study, as per self-reports, suggests compliance with the study conditions.

CONCLUSIONS

The results found in this proof of concept study warrant further systematic exploration of Sativex as a treatment option for cannabis withdrawal and dependence.

[Methamphetamine, cannabis]

The persons with marijuana abuse tend to be increasing in Japan, although illegal drugs use in lifetime is remarkably lower than other advanced countries, Europe and USA. In addition, there have been many methamphetamine users in Japan. As use of methamphetamine induces psychotic states, we recognize them as one of the key illegal drugs for clinical psychiatrists. Regarding to diagnosis of methamphetamine psychosis, there is a large difference between Japanese psychiatrists and other advanced countries' ones. The former considers that they have persistent symptoms. In contrast, the latter embraces it as the model of acute toxicosis. The Japanese government has been based on a full commitment to the crackdown on drug problems. However, they will execute the new law in 2016, in which some persons charged with violating the methamphetamine control law will be adapted to partially probation on drug charges. Then, we have to improve our therapeutic and recovery supports to charged illegal drug users as rapidly as possible.

[Cannabis--abuse and consequences]

Cannabis is the world's most popular illicit drug, and around half of all Danes have tried it at least once. In this paper we review the pharmacodynamic and pharmacokinetic properties of cannabis. We also discuss the treatment of cannabis intoxication and present data from The Danish Poison Information Center.

Plasma cannabinoid concentrations during dronabinol pharmacotherapy for cannabis dependence

BACKGROUND

Recently, high-dose oral synthetic delta-9-tetrahydrocannabinol (THC) was shown to alleviate cannabis withdrawal symptoms. The present data describe cannabinoid pharmacokinetics in chronic, daily cannabis smokers who received high-dose oral THC pharmacotherapy and later a smoked cannabis challenge.

METHODS

Eleven daily cannabis smokers received 0, 30, 60, or 120 mg/d THC for four 5-day medication sessions, each separated by 9 days of ad libitum cannabis smoking. On the fifth day, participants were challenged with smoking one 5.9% THC cigarette. Plasma collected on the first and fifth days was quantified by two-dimensional gas chromatography mass spectrometer for THC, 11-hydroxy-THC (11-OH-THC), and 11-nor-9-carboxy-THC (THCCOOH). Linear ranges (ng/mL) were 0.5-100 for THC, 1-50 for 11-OH-THC, and 0.5-200 for THCCOOH.

RESULTS

During placebo dosing, THC, 11-OH-THC, and THCCOOH concentrations consistently decreased, whereas all cannabinoids increased dose dependently during active dronabinol administration. THC increase over time was not significant after any dose, 11-OH-THC increased significantly during the 60- and 120-mg/d doses, and THCCOOH increased significantly only during the 120-mg/d dose. THC, 11-OH-THC, and THCCOOH concentrations peaked within 0.25 hours after cannabis smoking, except after 120 mg/d THC when THCCOOH peaked 0.5 hours before smoking.

CONCLUSIONS

The significant withdrawal effects noted during placebo dronabinol administration were supported by significant plasma THC and 11-OH-THC concentration decreases. During active dronabinol dosing, significant dose-dependent increases in THC and 11-OH-THC concentrations support withdrawal symptom suppression. THC concentrations after cannabis smoking were only distinguishable from oral THC doses for 1 hour, too short a period to feasibly identify cannabis relapse. THCCOOH/THC ratios were higher 14 hours after overnight oral dronabinol abstinence but cannot distinguish oral THC dosing from the smoked cannabis intake.

Pharmacotherapies for cannabis dependence

BACKGROUND

Cannabis is the most prevalent illicit drug in the world. Demand for treatment of cannabis use disorders is increasing. There are currently no pharmacotherapies approved for treatment of cannabis use disorders.

OBJECTIVES

To assess the effectiveness and safety of pharmacotherapies as compared with each other, placebo or supportive care for reducing symptoms of cannabis withdrawal and promoting cessation or reduction of cannabis use.

SEARCH METHODS

We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (to 4 March 2014), MEDLINE (to week 3 February 2014), EMBASE (to 3 March 2014) and PsycINFO (to week 4 February 2014). We also searched reference lists of articles, electronic sources of ongoing trials and conference proceedings, and contacted selected researchers active in the area.

SELECTION CRITERIA

Randomised and quasi-randomised controlled trials involving the use of medications to reduce the symptoms and signs of cannabis withdrawal or to promote cessation or reduction of cannabis use, or both, in comparison with other medications, placebo or no medication (supportive care) in participants diagnosed as cannabis dependent or who were likely to be dependent.

DATA COLLECTION AND ANALYSIS

We used standard methodological procedures expected by The Cochrane Collaboration. Two review authors assessed studies for inclusion and extracted data. All review authors confirmed the inclusion decisions and the overall process.

MAIN RESULTS

We included 14 randomised controlled trials involving 958 participants. For 10 studies the average age was 33 years; two studies targeted young people; and age data were not available for two studies. Approximately 80% of study participants were male. The studies were at low risk of selection, performance, detection and selective outcome reporting bias. Three studies were at risk of attrition bias.All studies involved comparison of active medication and placebo. The medications included preparations containing tetrahydrocannabinol (THC) (two studies), selective serotonin reuptake inhibitor (SSRI) antidepressants (two studies), mixed action antidepressants (three studies), anticonvulsants and mood stabilisers (three studies), an atypical antidepressant (two studies), an anxiolytic (one study), a norepinephrine reuptake inhibitor (one study) and a glutamatergic modulator (one study). One study examined more than one medication. Diversity in the medications and the outcomes reported limited the extent that analysis was possible. Insufficient data were available to assess the utility of most of the medications to promote cannabis abstinence at the end of treatment.There was moderate quality evidence that completion of treatment was more likely with preparations containing THC compared to placebo (RR 1.29, 95% CI 1.08 to 1.55; 2 studies, 207 participants, P = 0.006). There was some evidence that treatment with preparations containing THC was associated with reduced cannabis withdrawal symptoms and craving, but this latter outcome could not be quantified. For mixed action antidepressants compared with placebo (2 studies, 179 participants) there was very low quality evidence on the likelihood of abstinence from cannabis at the end of follow-up (RR 0.82, 95% CI 0.12 to 5.41), and moderate quality evidence on the likelihood of treatment completion (RR 0.93, 95% CI 0.71 to 1.21). For this same outcome there was very low quality evidence for the effects of SSRI antidepressants (RR 0.82, 95% CI 0.44 to 1.53; 2 studies, 122 participants), anticonvulsants and mood stabilisers (RR 0.78, 95% CI 0.42 to 1.46; 2 studies, 75 participants), and the atypical antidepressant, bupropion (RR 1.06, 95% CI 0.67 to 1.67; 2 studies, 92 participants). Available evidence on gabapentin (anticonvulsant) and N-acetylcysteine (glutamatergic modulator) was insufficient for quantitative estimates of their effectiveness, but these medications may be worth further investigation.

AUTHORS' CONCLUSIONS

There is incomplete evidence for all of the pharmacotherapies investigated, and for many of the outcomes the quality was downgraded due to small sample sizes, inconsistency and risk of attrition bias. The quantitative analyses that were possible, combined with general findings of the studies reviewed, indicate that SSRI antidepressants, mixed action antidepressants, atypical antidepressants (bupropion), anxiolytics (buspirone) and norepinephrine reuptake inhibitors (atomoxetine) are probably of little value in the treatment of cannabis dependence. Preparations containing THC are of potential value but, given the limited evidence, this application of THC preparations should be considered still experimental. Further studies should compare different preparations of THC, dose and duration of treatment, adjunct medications and therapies. The evidence base for the anticonvulsant gabapentin and the glutamatergic modulator N-acetylcysteine is weak, but these medications are also worth further investigation.

New approach to the neurobiological mechanisms of addiction

Much progress has been made in the last decade in the understanding the neural substrates of drug addiction, transmitters involved, epigenetic background and their relation to learning and memory but much remains to be elucidated and strong effort is necessary to integrate the rich information at the molecular, cellular systems, and behavioral levels to further clarify the mechanisms and therapy of this complex disease. The aim of this review is to collect and interpret the latest opinions in the development, the underlying mechanisms and therapy of addiction as a disease of central nervous system. The neurocircuitry, the transmitters and the epigenetics of addiction are discussed.

A human laboratory study investigating the effects of quetiapine on marijuana withdrawal and relapse in daily marijuana smokers

Marijuana withdrawal contributes to the high relapse rates in individuals seeking treatment for marijuana-use disorders. Quetiapine, an atypical antipsychotic, reduces characteristic symptoms of marijuana withdrawal in a variety of psychiatric conditions, including mood lability, sleep disruption and anorexia. This human laboratory study investigated the effectiveness of quetiapine to decrease marijuana withdrawal and relapse to marijuana use in non-treatment-seeking marijuana smokers. Volunteers were maintained on placebo or quetiapine (200 mg/day) in this double-blind, counter-balanced, within-subject study consisting of two 15-day medication phases, the last 8 days of which were in-patient. On the first in-patient day, active marijuana [6.2% delta (9)-tetrahydrocannabinol (THC)] was repeatedly smoked under controlled conditions. For the next 3 days, inactive marijuana (0.0% THC) was available for self-administration (withdrawal). On the subsequent 4 days, active marijuana (6.2% THC) was available for self-administration (relapse). Volunteers (n = 14) who smoked an average of 10 marijuana cigarettes/day, 7 days/week, completed the study. Under placebo, withdrawal was marked by increased subjective ratings of negative mood, decreased sleep quality, and decreased caloric intake and weight loss. Compared with placebo, quetiapine improved sleep quality, increased caloric intake and decreased weight loss. However, quetiapine increased marijuana craving and marijuana self-administration during the relapse phase. These data do not suggest that quetiapine shows promise as a potential treatment for marijuana dependence.

Subjective, cognitive and cardiovascular dose-effect profile of nabilone and dronabinol in marijuana smokers

Marijuana dependence is a substantial public health problem, with existing treatments showing limited efficacy. In laboratory and clinical studies, the cannabinoid receptor 1 agonist oral Δ9tetrahydrocannabinol (THC; dronabinol) has been shown to decrease marijuana withdrawal but not relapse. Dronabinol has poor bioavailability, potentially contributing to its failure to decrease relapse. The synthetic THC analogue, nabilone, has better bioavailability than dronabinol. We therefore aimed to characterize nabilone's behavioral and physiological effects across a range of acute doses in current marijuana smokers and compare these with dronabinol's effects. Participants (4 female; 10 male) smoking marijuana 6.6 (standard deviation = 0.7) days/week completed this outpatient, within-subjects, double-blind, randomized protocol. Over seven sessions, the time-dependent subjective, cognitive and cardiovascular effects of nabilone (2, 4, 6, 8 mg), dronabinol (10, 20 mg) and placebo were assessed. Nabilone (4, 6, 8 mg) and dronabinol (10, 20 mg) increased ratings of feeling a good effect, a strong effect and/or 'high' relative to placebo; nabilone had a slower onset of peak subjective effects than dronabinol. Nabilone (6, 8 mg) modestly lowered psychomotor speed relative to placebo and dronabinol. There were dose-dependent increases in heart rate after nabilone, and nabilone (2 mg) and dronabinol (10 mg) decreased systolic blood pressure. Thus, nabilone produced sustained, dose-related increases in positive mood, few cognitive decrements and lawful cardiovascular alterations. It had a longer time to peak effects than dronabinol, and effects were more dose-related, suggesting improved bioavailability. Nabilone was well tolerated by marijuana smokers, supporting further testing as a potential medication for marijuana dependence.

Nabilone decreases marijuana withdrawal and a laboratory measure of marijuana relapse

Few individuals seeking treatment for marijuana use achieve sustained abstinence. The cannabinoid receptor agonist, Δ(9)-tetrahydrocannabinol (THC; dronabinol), decreases marijuana withdrawal symptoms, yet does not decrease marijuana use in the laboratory or clinic. Dronabinol has poor bioavailability, which may contribute to its poor efficacy. The FDA-approved synthetic analog of THC, nabilone, has higher bioavailability and clearer dose-linearity than dronabinol. This study tested whether nabilone administration would decrease marijuana withdrawal symptoms and a laboratory measure of marijuana relapse relative to placebo. Daily, nontreatment-seeking marijuana smokers (8 men and 3 women), who reported smoking 8.3±3.1 marijuana cigarettes/day completed this within-subject study comprising three, 8-day inpatient phases; each phase tested a different nabilone dose (0, 6, 8 mg/day, administered in counter-balanced order on days 2-8). On the first inpatient day, participants took placebo capsules and smoked active marijuana (5.6% THC) at six timepoints. For the next 3 days, they had the opportunity to self-administer placebo marijuana (0.0% THC; withdrawal), followed by 4 days in which active marijuana was available for self-administration (5.6% THC; relapse). Both nabilone dose conditions decreased marijuana relapse and reversed withdrawal-related irritability and disruptions in sleep and food intake (p<0.05). Nabilone (8 mg/day) modestly worsened psychomotor task performance. Neither dose condition increased ratings of capsule 'liking' or desire to take the capsules relative to placebo. Thus, nabilone maintenance produced a robust attenuation of marijuana withdrawal symptoms and a laboratory measure of relapse even with once per day dosing. These data support testing of nabilone for patients seeking marijuana treatment.

Pregabalin and topiramate regulate behavioural and brain gene transcription changes induced by spontaneous cannabinoid withdrawal in mice

This study examined the actions of pregabalin and topiramate on behavioural and gene transcription alterations induced by spontaneous cannabinoid withdrawal in mice. Tolerance was induced in mice by administration of CP-55,940 (0.5 mg/kg/12 hours; i.p.; 7 days). Behavioural assessment of spontaneous cannabinoid withdrawal was performed by measuring motor activity, somatic signs and anxiety-like behaviour on days 1 and 3 after cessation of treatment with CP-55,940. On days 1-3 of cannabinoid withdrawal, mice received pregabalin (40 mg/kg/12 hours; p.o.) or topiramate (50 mg/kg/12 hours; p.o.) and their actions on signs of withdrawal and anxiety-like behaviour were evaluated. The administration of CP-55,940 decreased rectal temperature and motor activity on day 1. On day 1 after interruption of cannabinoid administration, motor activity and the number of rearings increased compared with control group. Anxiety-like behaviour induced by cessation of cannabinoid treatment increased significantly on days 1 and 3 of withdrawal. The administration of pregabalin or topiramate blocked the motor signs and reduced significantly anxiety-like behaviour. Cannabinoid withdrawal decreased tyrosine hydroxylase (TH) gene expression in the ventral tegmental area and µ-opioid receptor gene expression in the nucleus accumbens (NAcc) and increased CB1 receptor gene expression in the NAcc. Treatment with topiramate or pregabalin blocked the decrease of TH and the increase of CB1 gene expressions induced by cannabinoid withdrawal. Both drugs failed to alter µ-opioid receptor gene expression. These results suggest that pregabalin and topiramate may result useful for the treatment of anxiety-like behaviour and motor symptoms associated with spontaneous cannabinoid withdrawal.

[Levels of evidence in drug therapy for alcohol use disorders and illicit drug use]

Substance-related disorders are clinically and socially very important. In Germany over a million people of varying ages are affected. Depending on the substance and stage of treatment, drugs and different treatment methods are used. Through a literature search we examined the current knowledge of what drugs and therapies are used to date, and what randomised trials have been carried out to prove the efficacy of drug therapy. The aim was to define for each drug or pharmacological therapy a specific level of evidence. For the pharmacological treatment of alcohol, cocaine and opiate withdrawal syndromes and their relapses, prophylaxis or replacement therapy drugs are found to have a high level of evidence. Efficacy has been proven scientifically for processes such as behaviour therapy, contingency management or motivational interviewing.

[Six-month follow-up study of drug treatment for cannabis addiction: comparison study of four drugs]

OBJECTIVES

Marijuana addiction is one of the most common forms of addiction worldwide. A variety of reasons for use exist, however, there are only a few tested treatments with frequent relapses. In this study, we examined the efficacy of four pharmacotherapy agents for the treatment of marijuana addiction: naltrexone, bupropion, escitalopram and bromazepam.

MATERIALS AND METHODS

A total of 59 patients were randomly assigned into four groups. Each group received one of the pharmacological agents for 120 days. Four types of questionnaires were employed: The Hamilton Rating Scale for Depression--21 items, the Hamilton Rating Scale for Anxiety, the Global Assessment of Functioning and a Visual Analogue Scale for perceived need of the drug. In addition, random urine tests were performed to detect tetrahydrocannabinol [THC).

RESULTS

Naltrexone proved to be the most efficacious of the four agents, with only four dropouts. Other agents proved less efficacious with six, seven and eights dropouts for bupropion, bromazepam and escitalopram, respectively. In addition, naltrexone was most efficacious in reducing anxiety and depression rates, and increasing functioning and perceived need for drug use.

CONCLUSION

Out of four pharmacological agents, naltrexone proved to be most efficacious in treating marijuana addiction and related disorders. Further studies are needed to confirm our results.

[Clinical characteristics of cannabis-induced schizophrenia spectrum disorder]

Marijuana (cannabis) is the most commonly abused drug by adolescents and young adults and also by people with schizophrenia or other psychotic disorders. An increasing number of studies suggest that regular cannabis users can show psychotic episodes similar to schizophrenic disorders but it still unclear if cannabis induced psychotic disorder is a distinct entity requiring special therapy or regular cannabis use consequently leads to schizophrenia. Therefore, we retrospectively compared psychotic patients with and without cannabis use by clinical profile. Clinical data of 85 patients with schizophrenia spectrum disorder were analyzed retrospectively. Cannabis use was not reported by 43 persons (Cnbs0 subgroup) and 42 patients used regularly cannabis during at least 1 year (Cnbs1 subgroup). Clinical data were collected from electronic medical documentation of patients concerning anamnesis, family history, socio-demographic condition, symptoms and psychiatric state, acute and long-term therapies. Men were over-represented in the cannabis abuser group while mean age was lower among them compared to the Cnbs0 subgroup. Prevalence of suicidal attempts was increased in men without cannabis use. Patients without cannabis use spent more time in hospital and smoking was more frequent among them. Positive and negative symptoms and family history did not differ significantly between the two subgroups. Dosage, intensity and length of pharmacotherapy was different between the two subgroups. These results revealed that certain clinical aspects were different in case of cannabis-related schizophrenia spectrum disorder compared to schizophrenia.

Pharmacological treatment of cannabis dependence

Cannabis is the most frequently used illegal psychoactive substance in the world. There is a significant increase in the number of treatment admissions for cannabis use disorders in the past few years, and the majority of cannabis-dependent individuals who enter treatment have difficulty in achieving and maintaining abstinence. Thus, there is increased need for medications that can be used to treat this population. So far, no medication has been shown broadly and consistently effective; none has been approved by any national regulatory authority. Medications studied have included those that alleviate symptoms of cannabis withdrawal (e.g., dysphoric mood, irritability),those that directly affect endogenous cannabinoid receptor function, and those that have shown efficacy in treatment of other drugs of abuse or psychiatric conditions. Buspirone is the only medication to date that has shown efficacy for cannabis dependence in a controlled clinical trial. Results from controlled human laboratory studies and small open-label clinical trials suggest that dronabinol, the COMT inhibitor entacapone, and lithium may warrant further study. Recent pre-clinical studies suggest the potential of fatty acid amide hydrolase (FAAH) inhibitors such as URB597, endocannabinoid-metabolizing enzymes, and nicotinic alpha 7 receptor antagonists such as methyllycaconitine (MLA).Controlled clinical trials are needed to evaluate the clinical efficacy of these medications and to validate the laboratory models being used to study candidate medications.

[Cannabis use disorder and treatment of dependence]

Cannabis, known as marijuana, has been used illicit drug by young people in the world. In our country, the number of user for cannabis is recently increased gradually. It has been suggested that regular use of cannabis might induce several adverse effects such as dependence syndrome, because delta-9-tetrahydrocannabinol(THC), a primary psychoactive component of cannabis, stimulates brain-reward areas through the activation of cannabinoid(CB1) receptor and induce drug-seeking behavior. Therefore, it is necessary to investigate and establish the medications for cannabis dependence. In fact, controlled laboratory studies and small open-label clinical studies have shown that several candidates of medications for cannabinoid dependence are identified. Further investigation in controlled clinical trials may produce the therapeutic benefit for treatment about cannabis-related problems.

Concurrent Cannabis Use During Treatment for Comorbid ADHD and Cocaine Dependence: Effects on Outcome

Cannabis is the most widely used illicit substance in the United States with especially high prevalence of use among those with psychiatric disorders. Few studies have examined the relationship between concurrent cannabis use and treatment outcome among patients receiving treatment for comorbid substance abuse and psychiatric disorders. This study investigated the effects of cannabis use on treatment retention and abstinence from cocaine among cocaine dependent patients with Attention Deficit Hyperactivity Disorder (ADHD). Cocaine dependent patients diagnosed with current ADHD (DSM-IV, N = 92) aged 25 to 51 participated in a randomized clinical trial of methylphenidate for treatment of ADHD and cocaine dependence in an outpatient setting. The majority of patients (69%) used cannabis during treatment. Results suggest that moderate/intermittent cannabis users had greater retention rates compared to abstainers and consistent users (p = .02). This study is the first to examine concurrent cannabis use in cocaine dependent patients diagnosed with ADHD.

[Cannabis and cannabinoid receptors--abuse and psychosis]

Abuse of alcohol and drugs often co-occur with psychotic disorders. In this article, we introduce to the reader a number of receptors and neurotransmitter-systems involved in cannabis-abuse. Subsequently, we introduce the connection between abuse - particularly cannabis-abuse - and psychotic disorders.

[Future medications for tobacco and cannabis dependence]

Worldwide more than 3 million deaths a year are attributable to smoking, and tobacco use is on the rise in developing countries. Consequently, smoking is one of the few causes of mortality that is increasing, with deaths projected to reach 10 million annually in 30-40 years. Cannabinoids, which are usually used in the form of marijuana, have become the most frequently used illicit drugs, but there is no pharmacological treatment for marijuana dependence. Although the dopaminergic system plays a critical role in reinforcing the effects of drugs of abuse, other neurotransmitter systems are also involved. Here we review recent results obtained with antagonists targeting cannabinoid CB1 receptors, dopamine D3 receptors and opioid receptors, that directly or indirectly modulate dopaminergic transmission. These promising approaches warrant clinical trials in the treatment of tobacco and marijuana dependence.

Nicotinic alpha 7 receptors as a new target for treatment of cannabis abuse

Increasing use of cannabis makes the search for medications to reduce cannabis abuse extremely important. Here, we show that homomeric alpha7 nicotinic receptors are novel molecular entities that could be targeted in the development of new drugs for the treatment of cannabis dependence. In rats, systemic administration of the selective alpha7 nicotinic acetylcholine receptor antagonist methyllycaconitine (MLA), but not the selective heteromeric non-alpha7 nicotinic acetylcholine receptor antagonist dihydrobetaerythroidine, (1) antagonized the discriminative effects of delta-9-tetrahydrocannabinol (THC), the main active ingredient in cannabis, (2) reduced intravenous self-administration of the synthetic cannabinoid CB1 receptor agonist WIN55,212-2 [(R)-(+)-[2,3-dihydro-5-methyl-3[(4-morpholinyl)methyl]pyrrolo[1,2,3-de]-1,4-benzoxazinyl]-(1-naphthalenyl)methanone, mesylate salt], and (3) decreased THC-induced dopamine elevations in the shell of the nucleus accumbens. Altogether, our results indicate that blockade of alpha7 nicotinic receptors reverses abuse-related behavioral and neurochemical effects of cannabinoids. Importantly, MLA reversed the effects of cannabinoids at doses that did not produce depressant or toxic effects, further pointing to alpha7 nicotinic antagonists as potentially useful agents in the treatment of cannabis abuse in humans.

Safety, tolerability and efficacy of levodopa-carbidopa treatment for cocaine dependence: two double-blind, randomized, clinical trials

RATIONALE

The role of dopamine in cocaine abuse has been long recognized. Cocaine use can profoundly alter dopaminergic functioning through depletion of this monoamine and changes in receptor functioning. Based on these facts, levodopa (L-dopa) pharmacotherapy may be helpful in reducing or abolishing cocaine use.

OBJECTIVE

The current studies sought to evaluate the safety, tolerability and efficacy of L-dopa as a treatment for cocaine dependence.

METHODS

In Study 1, 67 cocaine-dependent subjects were randomized in a 5-week, double-blind, placebo-controlled safety trial. Subjects received either placebo, or 400 mg L-dopa plus 100 mg of the peripheral decarboxylase inhibitor, carbidopa, in a sustained-release preparation (Sinemet CR). In Study 2, 122 cocaine-dependent subjects were enrolled in a 9-week, randomized, double-blind, placebo-controlled trial to compare placebo to 400/100 mg and 800/200 mg L-dopa/carbidopa treatments. Placebo or L-dopa were administered twice daily in both studies.

RESULTS

L-dopa was well tolerated with similar retention and medication adherence rates compared to placebo. Only two side effects occurred more often in L-dopa-treated patients: nausea and dizziness. L-dopa lowered diastolic blood pressure in a dose-dependent fashion. In these trials, L-dopa had no effect on cocaine use, cocaine craving, or mood.

CONCLUSION

These two studies demonstrate the safety and tolerability of L-dopa pharmacotherapy in cocaine-dependent patients. No evidence for greater efficacy of L-dopa compared to placebo was observed. The possibility of enhancing treatment effects by combining L-dopa with other behavioral or pharmacological interventions is discussed.

An NMDA antagonist (LY 235959) attenuates abstinence-induced withdrawal of planarians following acute exposure to a cannabinoid agonist (WIN 55212-2)

The mechanisms that facilitate the development and expression of cannabinoid physical dependence in humans and other mammals are poorly understood. The present experiments used a planarian model to provide evidence that pharmacological antagonism of NMDA receptors significantly attenuates the development of cannabinoid physical dependence. Abstinence-induced withdrawal from the cannabinoid agonist WIN 55212-2 (10 microM) was manifested as a significant (P<0.05) decrease in the rate of planarian spontaneous locomotor velocity (pLMV) when WIN 55212-2 (10 microM)-exposed planarians were placed into drug-free water. No change in pLMV occurred when WIN 55212-2 (10 microM)-exposed planarians were placed into water containing WIN 55212-2 (10 microM). WIN 55212-2 (10 microM)-exposed planarians placed into water containing LY 235959 (1 or 10 microM) did not display withdrawal (no significant difference, P>0.05, in pLMV). In addition, withdrawal was not observed (no significant difference, P>0.05, in pLMV) in planarians that were co-exposed to a solution containing WIN 55212-2 (10 microM) and LY 235959 (10 microM). The present results reveal that NMDA receptor activation mediates the development of cannabinoid physical dependence and the expression of cannabinoid withdrawal in planarians.

Quetiapine in patients with comorbid schizophrenia-spectrum and substance use disorders: an open-label trial

BACKGROUND

Preliminary evidence suggests that clozapine relieves the craving for psychoactive substances in schizophrenia patients. Quetiapine shares crucial pharmacological properties with clozapine. Promising results have been described with quetiapine therapy in patients with psychosis and substance use disorder.

METHODS

Based on Diagnostic and Statistical Manual of Mental Disorders - fourth edition (DSM-IV) criteria, patients were diagnosed with comorbid schizophrenia-spectrum and substance use disorders. Patients were switched to quetiapine for a 12-week open-label trial. Craving, quantities used, days of consumption, and severity of substance abuse were assessed every 3 weeks. Alcohol and Drug Use Scales were administered on baseline and end-point. Psychiatric symptoms, depressive symptoms, extrapyramidal symptoms, and cognition were also assessed at baseline, week 6 and week 12.

RESULTS

Twenty-four schizophrenia-spectrum patients were included in the last observation carried forward (LOCF) analyses, responding to one or more of the following substance use disorders: cannabis (15 patients), alcohol (10 patients), and other psychoactive substances (nine patients). Overall, severity of substance abuse improved during the study. Less weekly days were spent on drugs of abuse. A decrease in the weekly Canadian dollars spent on psychoactive substances was also observed. Cognition, psychiatric, depressive, and extrapyramidal symptoms also significantly improved (p < 0.05).

CONCLUSIONS

In this open-label, uncontrolled trial, significant improvements were noted in substance abuse, psychiatric symptoms, extrapyramidal symptoms, and cognition during quetiapine therapy. The study suffered from three main limitations: (1) the open-label design of the study; (2) the patients' poor compliance; and (3) the small sample size involved. Controlled studies on the use of quetiapine in dual diagnosis schizophrenia are warranted to confirm that the effects are drug-related.