Alcohol Rehabilitation Within 3 Months After Alcohol Hepatitis and Survival - A National Analysis.

BACKGROUND & AIMS: There is limited understanding of the benefits of alcohol rehabilitation after alcohol hepatitis (AH). METHODS: We conducted a 2012 to 2021 national longitudinal study involving adult inpatients diagnosed with AH in France. We assessed the primary outcome of liver transplantation or death within 1 year after AH, including in its complicated form (CAH) defined as ≥2 hepatic or extrahepatic complications within 4 weeks after AH. The primary exposure was in-hospital alcohol rehabilitation within 3 months following AH. Patients who died (6.5%; n = 5282) or were censored (12.5%; n = 10,180) ≤4 weeks after AH were excluded. We measured adjusted hazard ratios (aHRs) and adjusted odds ratios (aORs) within the full cohort and propensity-matched samples. RESULTS: Among 65,737 patients (median age, 52 years; interquartile range [IQR], 44-60 years; 76% male), 12% died or underwent liver transplantation. In-hospital alcohol rehabilitation was noted for 25% of patients (15.2% among patients with CAH) and was the primary discharge diagnosis for 13.3%. The 1-year transplant-free survival rates were 94% (95% confidence interval [CI], 94%-95%) for rehabilitated patients, compared with 85% (95% CI, 85%-86%) for those without (aHR, 0.62; 95% CI, 0.57-0.69; P < .001). Among patients with CAH, transplant-free survival was 78% (95% CI, 76%-81%) with rehabilitation vs 70% (95% CI, 69%-71%) without (aHR, 0.82; 95% CI, 0.68-0.98; P = .025). In propensity-matched samples, rehabilitation was linked to an aOR of 0.54 (95% CI, 0.49-0.55; P < .001) overall, and 0.73 (95% CI, 0.60-0.89; P = .002) among matched patients with CAH. CONCLUSIONS: In-hospital alcohol rehabilitation within 3 months after AH and CAH improve transplant-free survival rate but remain underutilized.

Reduction of alcohol use and increase in psychological flexibility after a naturalistic psychedelic experience: a retrospective survey.

INTRODUCTION: Alcohol use can be significantly associated with negative social, professional, and health outcomes. Even more so, alcohol use disorder (AUD) is a critical public health issue and major avoidable risk factor. This study aimed to examine the effect of a naturalistic psychedelic experience on alcohol use and related measures. METHODS: A retrospective online survey was conducted on 160 individuals who reported a psychedelic experience and a concomitant drinking habit but did not necessarily have an AUD. Demographic data, characteristics of the psychedelic experience, and changes in alcohol consumption and psychological flexibility were surveyed. Results: The mean number of drinking days per week and AUDIT scores significantly decreased after the psychedelic experience (P < .001). Subjects who quit or reduced drinking had a more severe AUD (P < .01) and lower psychological flexibility (P = .003) before the psychedelic session. Alcohol use reduction was significantly associated with the intensity of the mystical experience (P = .03). Psychological flexibility increased more in participants who reduced their alcohol use (P < .001), and the change in psychological flexibility was one of the predictors of alcohol use improvement (P = .003). Conclusion: Our findings suggest that a naturalistic psychedelic experience could be associated with a reduction in alcohol use and dependency. Such positive health outcomes can be associated with the intensity of the mystical experience as well as an increase in psychological flexibility.

Increased markers of inflammation after cannabis cessation and their association with psychotic symptoms.

INTRODUCTION: A dysbalance of the immune system in psychotic disorders has been well investigated. However, despite a higher prevalence of cannabis (THC) consumption in patients with psychosis, few studies have investigated the impact of this use on inflammatory markers. METHODS: One hundred and two inpatients were included in this retrospective study. Leukocytic formula, hsCRP, fibrinogen levels and urinary THC were measured, and comparisons were performed at baseline and after 4 weeks of cannabis cessation between cannabis users (THC+) and non-users (THC-). RESULTS: After cannabis cessation, we found a greater increase in leucocyte level (p < 0.01), monocyte level (p = 0.05) and a statistical trend to a highest increase of lymphocyte level (p = 0.06) between baseline and 4 weeks in the THC+ group as compared to the THC- group. At 4 weeks, highest leucocyte (p = 0.03), lymphocyte (p = 0.04) and monocyte (p < 0.01) counts were found in the THC+ group, whereas at baseline no difference was found. A positive correlation was found between monocyte count at 4 weeks and baseline Positive and Negative Syndrome Scale (PANSS) negative subscore (p = 0.045) and between the variation of monocyte count between baseline and 4 weeks and the PANSS total score at 4 weeks (p = 0.05). CONCLUSION: THC cessation is associated with an increase in inflammatory markers, including white blood cell, lymphocyte and monocyte levels, which correlates with symptomatology of patients with psychosis.

[Neuroimaging correlates of classical psychedelics effects: A systematic review]. / Corolaires en neuro-imagerie des effets des psychédéliques classiques : une revue systématique de la littérature.

BACKGROUND: Current scientific literature supports classical psychedelic efficacy in many psychiatric disorders. However, less attention has been given to the neurological effects of these substances. The aim of this medical thesis was to conduct a systematic review examining the neuroimaging correlates of the effects of psychedelics. METHOD: We performed an electronic research through Medline and Science Direct databases. A comprehensive search yielded 460 articles published up to May 2022. After a cautious screening process, we selected 49 scientific papers for further analysis. RESULTS: Major findings included reduced functional network integration, increased between-network functional connectivity, and expansion of functional connectivity patterns repertoire under psychedelics. Thalamic gating and emotional processing were also impaired. These results positively correlated with symptom improvement in pathological populations. CONCLUSION: To this day, our knowledge concerning psychedelic effects remains partial. Several neurocognitive theories have been developed in recent years to model psychedelic phenomenology, but no unifying theory has emerged. Studies involving larger populations investigating various psychiatric disorders, including several neuroimaging modalities and considering medium- and long-term effects, would be necessary to deepen current knowledge.

Opinions of French psychiatrists on the regulatory status of cannabis: Results from the "PsyCan - Encéphale" national online survey.

OBJECTIVE: To explore the opinions of French psychiatrists toward the legalization of medical or recreational use of cannabis in France. METHODS: Psycan was an anonymous Internet survey conducted between September 28, 2021 and March 29, 2022, among subscribers of the Encéphale Online community, i.e., approximately 4000 French psychiatrists. Participants were asked to complete a structured questionnaire, collecting their socio-demographic features, clinical experience, opinions toward cannabis legalization, and perceived impact of cannabis derivatives for psychiatric disorders. Logistic regression models were used to identify factors associated with being for or against cannabis legalization. RESULTS: In total, 413 psychiatrists answered the survey, of whom 253 (61.3%) declared being in favour of recreational cannabis, and 349 (84.4%) of medical cannabis. Being in favour of legalization of recreational cannabis was negatively associated with being female (odd ratio [OR]=0.61; 95% confidence interval [CI]=0.41-0.93), and with the frequency of meeting patients with cannabis use disorder (OR=0.60; 95%CI=0.43-0.83). Most respondents were concerned about the development of psychotic disorders. The most frequent pro-legalization arguments were improved prevention, better control of product content, and better protection of youth, respectively. Arguments against legalization were increased societal damages, increased impact on health, including mental health. CONCLUSIONS: A majority of French psychiatrists were in favour of the marketing of medical cannabis, and, to a lesser extent, the legalization of recreational cannabis. For recreational cannabis, the proportion of pro-legalization psychiatrists was slightly more elevated than that found in the French general population.

Sodium Oxybate for Alcohol Dependence: A Network Meta-Regression Analysis Considering Population Severity at Baseline and Treatment Duration.

AIMS: The estimated effect of sodium oxybate (SMO) in the treatment of alcohol dependence is heterogeneous. Population severity and treatment duration have been identified as potential effect modifiers. Population severity distinguishes heavy drinking patients with <14 days of abstinence before treatment initiation (high-severity population) from other patients (mild-severity population). Treatment duration reflects the planned treatment duration. This study aimed to systematically investigate the effect of these potential effect moderators on SMO efficacy in alcohol-dependent patients. METHODS: Network meta-regression allows for testing potential effect modifiers. It was selected to investigate the effect of the above factors on SMO efficacy defined as continuous abstinence (abstinence rate) and the percentage of days abstinent (PDA). Randomized controlled trials for alcohol dependence with at least one SMO group conducted in high-severity and mild-severity populations were assigned to a high-severity and mild-severity group of studies, respectively. RESULTS: Eight studies (1082 patients) were retained: four in the high-severity group and four in the mild-severity group. The high-severity group was associated with larger SMO effect sizes than the mild-severity group: abstinence rate risk ratio (RR) 3.16, P = 0.004; PDA +26.9%, P < 0.001. For PDA, longer treatment duration was associated with larger SMO effect size: +11.3% per extra month, P < 0.001. In the high-severity group, SMO showed benefit: abstinence rate RR 2.91, P = 0.03; PDA +16.9%, P < 0.001. In the mild-severity group, SMO showed benefit only in PDA for longer treatment duration: +23.9%, P < 0.001. CONCLUSIONS: In the retained studies with alcohol-dependent patients, high-severity population and longer treatment duration were associated with larger SMO effect sizes.

White blood cells and patients with psychiatric disorders needing seclusion: A retrospective non-interventional study.

OBJECTIVE: The objective of this retrospective study was to investigate the peripheral immunological markers using leucocyte count, the neutrophil to lymphocyte ratio (NLR), the platelet to lymphocyte ratio (PLR), and the monocyte to lymphocyte ratio (MLR) in patients with aggressive behavior, during and after seclusion. METHODS: Ninety-nine inpatients were included in this retrospective study. Leucocyte count was measured, and NLR, PLR and MLR were calculated and compared between a group of patients who required seclusion and a group who did not. A multivariate analysis was performed using binary logistic regression, including confounding factors such as age, gender, medication, BMI, smoking status and diagnosis. RESULTS: We found the lowest levels of lymphocytes (P=0.01) and basophils (P<0.01) and the highest NLR (P=0.02) and MLR (P=0.04) in the seclusion group. We also found a restoration of these parameters after the end of the seclusion period. Furthermore, we found a positive correlation between the PANSS negative subscore, and PLR (P=0.05), or MLR (P=0.03) after seclusion, and between the MLR variation across the seclusion period and the PANSS general subscore after the end of seclusion (P=0.04). CONCLUSION: This study shows that NLR and MPR are higher in patients with aggressive symptoms and/or agitation who require seclusion. These immunological markers could be considered as state markers.

[Women and alcohol, the addictologist's point of view and treatment]. / Les femmes et l'alcool, point de vue de l'addictologue et prise en charge.

Women have difficulty seeking help for alcohol-related problems. Shame and guilt are often present, which is why the caregiver must succeed in establishing a climate of trust so that things can be said, in order to best assess the impact of consumption and find alternatives. Treatment is often multidisciplinary. The nurse's role is essential, not only to identify drug use, but also to provide a link between the various players involved.

Management of alcohol-related liver disease: the French Association for the Study of the Liver and the French Alcohol Society clinical guidelines.

Excessive alcohol consumption is the leading cause of liver diseases in Western countries, especially in France. Alcohol-related liver disease (ARLD) is an extremely broad context and there remains much to accomplish in terms of identifying patients, improving prognosis and treatment, and standardising practices. The French Association for the Study of the Liver wished to organise guidelines together with the French Alcohol Society in order to summarise the best evidence available about several key clinical points in ARLD. These guidelines have been elaborated based on the level of evidence available in the literature and each recommendation has been analysed, discussed and voted by the panel of experts. They describe how patients with ARLD should be managed nowadays and discuss the main unsettled issues in the field.

One-month alcohol abstinence national campaigns: a scoping review of the harm reduction benefits.

Over the last decade, one-month alcohol abstinence campaigns (OMACs) have been implemented within the general population in an increasing number of countries. We identified the published studies reporting data on OMACs to explore the following aspects: profile of participants, rates and factors associated with the completion of the abstinence challenge, and outcomes and harm reduction benefits in participating in the challenges. We screened 322 records, including those found in the grey literature, and reviewed 6 studies and 7 Dry July Annual Reports. Compared to non-participating alcohol users, participants were more likely to be female, have a higher income, and a higher level of education. They were heavier drinkers and were more concerned by the consequences of alcohol on health and by their health in general. Participants who achieved the one-month abstinence challenge were lower drinkers and more likely to have registered on the campaign-related Internet communities. Both successful and unsuccessful participants frequently reported health benefits, including sleep improvement and weight loss. Successful participants were more likely to durably change their alcohol drinking habits. Overall, OMACs provide short- or mid-term harm reduction benefits for both successful and unsuccessful participants. Findings were limited by the paucity of studies, their observational nature, and heterogeneity in the features of the different national campaigns, which would probably gain in enhanced internationalization.

Cannabis Cessation, Inflammatory Markers and Schizophrenia.

Objective A dysbalance of the immune system in schizophrenia has been largely described but few studies have investigated the impact of cannabis use on inflammatory markers in patients with schizophrenia. The objective of our study was to investigate the impact of cannabis use on high-sensitivity C-reactive protein (hsCRP), fibrinogen levels and leucocytic formula in patients with schizophrenia. Methods: Thirty-eight acutely ill inpatients with schizophrenia were included. Patient hsCRP, fibrinogen levels, leukocytic formula and urinary cannabis were measured at baseline and after four weeks of treatment. Results: After four weeks of cannabis cessation (as confirmed by urinary tests), we found an increase of hsCRP level (p = .016) and lymphocytes (p = .03) in consumers patients whereas no difference was observed in non-consumers patients. As compared to non-consumers patients with schizophrenia, consumers had lower levels of hsCRP (p = .045). Finally, a negative correlation was found between the PANSS score evolution (between baseline and 4 weeks) and baseline hsCRP level. Conclusions: In our study, cannabis cessation raises inflammatory markers though improving clinical symptoms. The investigation and the understanding of interactions between cannabis use and inflammatory markers in patients with schizophrenia is of importance and could in the future be a new target for treatment of psychiatric symptoms linked to inflammation.

Baseline severity and the prediction of placebo response in clinical trials for alcohol dependence: A meta-regression analysis to develop an enrichment strategy.

BACKGROUND: There is considerable unexplained variability in alcohol abstinence rates (AR) in the placebo groups of randomized controlled trials (RCTs) for alcohol dependence (AD). This is of particular interest because placebo responses correlate negatively with treatment effect size. Recent evidence suggests that the placebo response is lower in very heavy drinkers who show no "spontaneous improvement" prior to treatment initiation (high-severity population) than in a mild-severity population and in studies with longer treatment duration. We systematically investigated the relationship between population severity, treatment duration, and the placebo response in AR to inform a strategy aimed at reducing the placebo response and thereby increasing assay sensitivity in RCTs for AD. METHODS: We conducted a systematic literature review on placebo-controlled RCTs for AD.We assigned retained RCTs to high- or mild-severity groups of studies based on baseline drinking risk levels and abstinence duration before treatment initiation. We tested the effects of population severity and treatment duration on the placebo response in AR using meta-regression analysis. RESULTS: Among the 19 retained RCTs (comprising 1996 placebo-treated patients), 11 trials were high-severity and 8 were mild-severity RCTs. The between-study variability in AR was lower in the high-severity than in the mild-severity studies (interquartile range: 7.4% vs. 20.9%). The AR in placebo groups was dependent on population severity (p = 0.004) and treatment duration (p = 0.017) and was lower in the high-severity studies (16.8% at 3 months) than the mild-severity studies (36.7% at 3 months). CONCLUSIONS: Pharmacological RCTs for AD should select high-severity patients to decrease the magnitude and variability in the placebo effect and and improve the efficiency of drug development efforts for AD.

Impact of alcohol marketing on drinkers with Alcohol use disorders seeking treatment: a mixed-method study protocol.

BACKGROUND: The marketing of alcohol influences patterns of alcohol consumption. Existing studies have focused, for the most part, on adolescents and the links between exposure to marketing and alcohol initiation. In France, the Evin law, a French exception, was set up in 1991 with the aim of regulating this exposure to marketing, but since 2009 it has been severely compromised. Alcohol consumption causes severe damage, which may be seenfrom 1 standard unit per day and mostly among adults who are regular users of alcohol. In this at-risk population, studies analysing the impact of marketing are sparse. The specific objectives include (i) the evaluation of the perception of alcohol marketing by patients with an AUD (ii) gaining understanding of the links between alcohol marketing and patients with AUD behaviours (iii) the development of alcohol demarketing strategy in patients receiving AUD coaching. METHODS: Our main objective isto evaluate the impact of marketing on a population with an AUD. The methodology was in 4 steps: step 1 is a pre-test (N = 100) selecting type of alcohol consumed and type of marketing stimuli identified by patients aged 18 + with an AUD. Step 2 is a qualitative study (N = 20), with in-depth interview, to understand links between alcohol marketing and patients with AUD behaviours. Step 3 is a quantitative study(N = 600) to confirm these links and the impact of alcohol marketing on patients with AUD behaviours. Step 4 is an interventional step, including and testing the impact of demarketing intervention on patients with AUD while using the results of the three first steps (N = 120). DISCUSSION: This study will contribute to a better definition of the impact of alcohol marketing on patients with AUD and will enable identification of the determinants of this impact. These data will inform the development of interventions that take into account demarketingstrategies on patients under AUD management. TRIAL REGISTRATION: The Trial registrationregistration number is NCT03876132, and it was registered on the 15th march 2019.

Cannabidiol affects circadian clock core complex and its regulation in microglia cells.

Cannabis is often used by consumers for sleep disorders. Studies show that circadian rhythm could be affected by a misuse of cannabis. Recent research has connected the role of microglial cells with psychiatric disorders such as substance abuse. The aim was to show the effect of two major components of cannabis on circadian genes regulation in microglial cells. In BV-2 microglial cells, cannabidiol (CBD) induces a deregulation of circadian genes with (P-value = 0.039) or without (P-value = 0.0015) lipopolisaccharides stimulation. CBD up regulated Arntl (P = 9.72E-5) and down regulated Clock (P = 0.0034) in BV-2 cells. Temporal expression of Arntl (light and dark P = 0.0054) and Clock (light and dark P = 0.047) was confirmed to have 24 hours light and dark rhythmic regulation in dissected suprachiasmatic nucleus as well as of Cb1 cannabinoid receptor (light and dark P = 0.019). In BV-2 microglia cells, CBD also up regulated CRY2 (P = 0.0473) and PER1 (P = 0.0131). Other nuclear molecules show a deregulation of circadian rhythm in microglial cells by CBD, such as RORA, RevErbα, RORB, CREBBP, AFT4, AFT5 and NFIL3. Our study suggests that circadian rhythm in microglial cells is deregulated by CBD but not by THC. It is consistent with clinical observations of the use of therapeutic cannabis to treat insomnia.

Kinetics of Cytokine Levels during Antipsychotic Treatment in Schizophrenia: A Meta-Analysis.

Background: Immune system dysfunction is a hypothesis in the psychopathology of schizophrenia, but the impact of antipsychotic treatment within this system is not clear. The aim of this meta-analysis was to investigate the impact of antipsychotic treatment on cytokine levels in in vivo studies on schizophrenia. Methods: After a systematic database search, original data were extracted with the help of certain authors. Means and SDs were extracted to calculate standardized mean differences. Cytokine levels were compared in vivo in schizophrenia patients, before and after antipsychotic treatment. Meta-regressions were performed to explore the influence of demographic and clinical variables on cytokine level standardized mean differences. Stratifications by treatment and diagnosis were also performed. Results: Forty-seven studies were included in this meta-analysis. Proinflammatory cytokine level decreases were found for interleukin-1 ß levels (P<.0001) and interferon-γ (P=.01) and a statistical trend towards a decrease in interleukin-6 (P=.08) and tumor necrosis factor-α (P=.07) levels. An antiinflammatory cytokine level increase was found for soluble tumor necrosis factor-R2 (P<.001) and soluble interleukin 2-R (P=.03) levels. A meta-regression analysis found a correlation between interleukin-6 level standardized mean differences and positive schizophrenia symptom score standardized mean differences before and after treatment (P=.01). Stratification by diagnosis or treatment found a possible impact of the kinetics of cytokine levels. Conclusions: The present meta-analysis provides evidence that antipsychotic treatment has an antiinflammatory effect and could normalize immune balance dysfunction in schizophrenia. Interleukin-6 level normalization could be a marker of illness equilibration and thus used in clinical practice.

Alcohol consumption, drinker identity, and quality of life among students: why there cannot be one prevention strategy for all.

INTRODUCTION: The objective for this study was to combine drinking characteristics and two subjective measures, drinker identity and alcohol-related quality of life, i.e., negative impact of alcohol on quality of life, to determine relevant profiles for indicated prevention programs. In particular, we hypothesized that different profiles of students with high level of alcohol consumption exist when exploring subjectivity. METHODS: We performed an online survey among 16,930 students. We collected sociodemographics and environmental data, including alcohol-related quality of life, drinker identity, and drinking characteristics. We performed a hierarchical clustering on principal components. We described all variables in each cluster and explored between clusters differences by Kruskal-Wallis tests. RESULTS: We identified five clusters as regarding drinker identity, drinking characteristics, and alcohol-related quality of life. Among these five clusters, three clusters presented high drinking characteristics. A very vulnerable cluster showed high level of alcohol consumption, impact on quality of life and on academic results, and strong drinker identity. An egodystonic cluster showed high level of consumption, mild impact on quality of life and on academic results, but low drinker identity. A cluster seemed short-term super-adapted in heavy drinking environment, showing high level of alcohol consumption and drinker identity, but low impact on quality of life and on academic results (all between clusters p values < 0.001 with Kruskal-Wallis tests). CONCLUSION: The subjective experience of students from these clusters was significantly different (p value < 0.001), and could explain some inadequacy of certain prevention strategies, considering binge drinker student as a homogeneous group. Prospective studies are needed to explore changes over time of these clusters.

Efficacy and safety of sodium oxybate in alcohol-dependent patients with a very high drinking risk level.

Medication development for alcohol relapse prevention or reduction of consumption is highly challenging due to methodological issues of pharmacotherapy trials. Existing approved medications are only modestly effective with many patients failing to benefit from these therapies. Therefore, there is a pressing need for other effective treatments with a different mechanism of action, especially for patients with very high (VH) drinking risk levels (DRL) because this is the most severely affected population of alcohol use disorder patients. Life expectancy of alcohol-dependent patients with a VH DRL is reduced by 22 years compared with the general population and approximately 90 000 alcohol-dependent subjects with a VH DRL die prematurely each year in the EU (Rehm et al. ). A promising new medication for this population is sodium oxybate, a compound that acts on GABAB receptors and extrasynaptic GABAA receptors resulting in alcohol-mimetic effects. In this article, a European expert group of alcohol researchers and clinicians summarizes data (a) from published trials, (b) from two new-as yet unpublished-large clinical trials (GATE 2 (n = 314) and SMO032 (n = 496), (c) from post hoc subgroup analyses of patients with different WHO-defined DRLs and (d) from multiple meta-analyses. These data provide convergent evidence that sodium oxybate is effective especially in a subgroup of alcohol-dependent patients with VH DRLs. Depending on the study, abstinence rates are increased up to 34 percent compared with placebo with risk ratios up to 6.8 in favor of sodium oxybate treatment. These convergent data are supported by the clinical use of sodium oxybate in Austria and Italy for more than 25 years. Sodium oxybate is the sodium salt of γ-hydroxybutyric acid that is also used as a recreational (street) drug suggestive of abuse potential. However, a pharmacovigilance database of more than 260 000 alcohol-dependent patients treated with sodium oxybate reported very few adverse side effects and only few cases of abuse. We therefore conclude that sodium oxybate is an effective, well-tolerated and safe treatment for withdrawal and relapse prevention treatment, especially in alcohol-dependent patients with VH DRL.

[Psychiatric and addictologic complications of new synthetic products]. / Complications psychiatriques et addictologiques des nouveaux produits de synthèse.

Psychiatric and addictologic complications of new synthetic products. New synthetic products (NSP) have completely changed the current scene of addictions. Also known as designer drugs, legal highs, herbal highs, bath salts, plant fertilizers, incense, research chemicals, they have made their emergence on the drug market in the late 1990s. Legal or herbal highs consist of uncontrolled psychoactive substances, obtained by chemical synthesis or derived from plants. Essentially produced in China and India, but also in Europe, their diffusion brings new communication technologies, fixes the offer and directs the users' demand on this specific market. They are mostly sold over the Internet and are generally a "legal" pseudo- alternative to controlled and regulated psychoactive products. They are consumed because of their effects mimicking those of an illicit substance such as cocaine, amphetamine, methamphetamine, cannabis, opioids for example. NSP induce numerous psychiatric, somatic, addictologic and social complications.

Complications psychiatriques et addictologiques des nouveaux produits de synthèse. Les nouveaux produits de synthèse ont complètement modifié la scène actuelle des addictions. Dénommés également designer drugs, legal highs ou euphorisants légaux, herbal highs ou euphorisants végétaux, sels de bain ou bath salts, engrais pour plantes, encens, produit chimique pour la recherche non consommable par l'homme ou research chemicals, les nouveaux produits de synthèse ont fait leur apparition sur le marché des drogues à la fin des années 1990. Les euphorisants légaux et végétaux correspondent à des substances psychoactives non contrôlées, obtenues par synthèse chimique ou dérivées de plantes. Essentiellement produits en Chine et en Inde, mais également en Europe, leur diffusion met en jeu les nouvelles technologies de communication, fixe l'offre et oriente la demande des usagers sur ce marché spécifique. Aujourd'hui, ces produits sont essentiellement vendus sur Internet et constituent généralement une pseudo-alternative « légale ¼ aux produits psychoactifs contrôlés et réglementés. Ils sont consommés en raison de leurs effets mimant ceux d'une substance illicite comme la cocaïne, les amphétamines, la méthamphétamine, le cannabis, les opioïdes par exemple. Ces nouveaux produits de synthèse sont source de nombreuses complications psychiatriques, somatiques, addictologiques et sociales.