A Review of Hallucinogen Persisting Perception Disorder (HPPD) and an Exploratory Study of Subjects Claiming Symptoms of HPPD

Hallucinogen persisting perception disorder (HPPD) is rarely encountered in clinical settings. It is described as a re-experiencing of some perceptual distortions induced while intoxicated and suggested to subsequently cause functional impairment or anxiety. Two forms exist: Type 1, which are brief "flashbacks," and Type 2 claimed to be chronic, waxing, and waning over months to years. A review of HPPD is presented. In addition, data from a comprehensive survey of 20 subjects reporting Type-2 HPPD-like symptoms are presented and evaluated. Dissociative Symptoms are consistently associated with HPPD. Results of the survey suggest that HPPD is in most cases due to a subtle over-activation of predominantly neural visual pathways that worsens anxiety after ingestion of arousal-altering drugs, including non-hallucinogenic substances. Individual or family histories of anxiety and pre-drug use complaints of tinnitus, eye floaters, and concentration problems may predict vulnerability for HPPD. Future research should take a broader outlook as many perceptual symptoms reported were not first experienced while intoxicated and are partially associated with pre-existing psychiatric comorbidity.

d-Lysergic acid diethylamide, psilocybin, and other classic hallucinogens: Mechanism of action and potential therapeutic applications in mood disorders

Depression and anxiety are psychiatric diagnoses commonly associated with low quality of life and low percentage of responsiveness by patients treated with currently available drugs. Thus, research into alternative compounds to treat these disorders is essential to guarantee a patient's remission. The last decade has witnessed a revamped interest for the application of psychedelic medicine for the treatment of mental disorders due to anecdotal reports and clinical studies which show that low doses of d-lysergic acid diethylamide (LSD) and psilocybin may have antidepressant effects. LSD and psilocybin have demonstrated mood-modulating properties likely due to their capacity to modulate serotonergic (5-HT), dopaminergic (DA) and glutamatergic systems. LSD, belonging to the category of "classic halluginogens," interacts with the 5-HT system through 5HT_1A, and 5HT_2A receptors, with the DA system through D₂ receptors, and indirectly also the glutamatergic neurotransmission thought the recruitment of N-methyl-d-aspartate (NMDA) receptors. Randomized clinical studies have confirmed its antidepressant and anxiolytic effects in humans. Thus, in this chapter, we will review the pharmacology of psychedelic drugs, report the most striking clinical evidence which substantiate the therapeutic potentials of these fascinating compounds in mood disorders, and look into the horizon of where psychedelic medicine is heading.

Neurotoxicity screening of new psychoactive substances (NPS): Effects on neuronal activity in rat cortical cultures using microelectrode arrays (MEA)

While the prevalence and the use of new psychoactive substances (NPS) is steadily increasing, data on pharmacological, toxicological and clinical effects is limited. Considering the large number of NPS available, there is a clear need for efficient in vitro screening techniques that capture multiple mechanisms of action. Neuronal cultures grown on multi-well microelectrode arrays (mwMEAs) have previously proven suitable for neurotoxicity screening of chemicals, pharmaceuticals and (illicit) drugs. We therefore used rat primary cortical cultures grown on mwMEA plates to investigate the effects of eight NPS (PMMA, α-PVP, methylone, MDPV, 2C-B, 25B-NBOMe, BZP and TFMPP) and two 'classic' illicit drugs (cocaine, methamphetamine) on spontaneous neuronal activity. All tested drugs rapidly and concentration-dependently decreased the weighted mean firing rate (wMFR) and the weighted mean burst rate (wMBR) during a 30 min acute exposure. Of the 'classic' drugs, cocaine most potently inhibited the wMFR (IC₅₀ 9.8 μM), whereas methamphetamine and the structurally-related NPS PMMA were much less potent (IC₅₀ 100 μM and IC₅₀ 112 μM, respectively). Of the cathinones, MDPV and α-PVP showed comparable IC₅₀ values (29 μM and 21 μM, respectively), although methylone was 10-fold less potent (IC₅₀ 235 μM). Comparable 10-fold differences in potency were also observed between the hallucinogenic phenethylamines 2C-B (IC₅₀ 27 μM) and 25B-NBOMe (IC₅₀ 2.4 μM), and between the piperazine derivatives BZP (IC₅₀ 161 μM) and TFMPP (IC₅₀ 19 μM). All drugs also inhibited the wMBR and concentration-response curves for wMBR and wMFR were comparable. For most drugs, IC₅₀ values are close to the estimated human brain concentrations following recreational doses of these drugs, highlighting the importance of this efficient in vitro screening approach for classification and prioritization of emerging NPS. Moreover, the wide range of IC₅₀ values observed for these and previously tested drugs of abuse, both within and between different classes of NPS, indicates that additional investigation of structure-activity relationships could aid future risk assessment of emerging NPS.

Self-Experiments with Psychoactive Substances: A Historical Perspective

The purpose of this chapter is to highlight the rich tradition of self-experiments (SEs) with psychoactive substances carried out by scientists and therapists for more than a century. Scientifically inspired controlled SEs dominated until the end of the twentieth century, when ethical requirements minimized controlled SEs and "wild" SEs expanded particularly with the emergence of new psychoactive substances. The review focuses on laughing gas (nitrous oxide), cannabis, cocaine, hallucinogens, entactogens, and dissociative hallucinogens. This is due to the fact that substances that induce "complex" effects such as alteration of space/time experience, ego dissolution, and increased feelings and insights (e.g., hallucinogens, entactogens) represent by far the majority of SEs, whereas SEs with substances inducing "simple" effects such as euphoria, anxiolysis, dissociation, or emotional blunting (e.g., cocaine, opioids) are much rarer or even absent (e.g., benzodiazepines). Complex drug effects are much harder to describe, thus allowing SEs to fulfill a more important function.SEs with psychoactive drugs appeared to emerge in the mid-eighteenth century, which triggered a long-standing tradition throughout the nineteenth and early twentieth century. SEs have been de facto performed for a variety of reasons, ranging from establishing scientific knowledge and gaining philosophical insights to compensating for personal deficits. Self-experimenters can be divided into two general types. Besides their scientific intentions, "exploratory" self-experimenters intend to expand awareness and insight, whereas "compensatory" self-experimenters might aim for coping with psychiatric symptoms or personality deficits. Scientific limitations of SEs are obvious when compared to double-blind, randomized, placebo-controlled trials. Whereas the former might lead to more "realistic" detailed description of subjective effects, the latter lead to more solid results in respect to objectively measurable "average" effects. Possible adverse effects of SEs were identified that resulted in loss of scientific objectivity and decreased control over substance use and addiction, development of isolation, problematic group dynamics, and "social autism."

The Discriminative Stimulus Properties of Hallucinogenic and Dissociative Anesthetic Drugs

The subjective effects of drugs are related to the kinds of feelings they produce, such as euphoria or dysphoria. One of the methods that can be used to study these effects is the drug discrimination procedure. Many researchers have been trying to elucidate the mechanisms that underlie the discriminative stimulus properties of abused drugs (e.g., alcohol, psychostimulants, and opioids). Over the past two decades, patterns of drug abuse have changed, so that club/recreational drugs such as phencyclidine (PCP), 3,4-methylenedioxymethamphetamine (MDMA), ketamine, and cannabinoid, which induce perceptual distortions, like hallucinations, are now more commonly abused, especially in younger generations. In particular, the abuse of designer drugs, which aim to mimic the subjective effects of psychostimulants (e.g., MDMA or amphetamines), has been problematic. However, the mechanisms of the discriminative stimulus effects of hallucinogenic and dissociative anesthetic drugs are not yet fully clear. This chapter focuses on recent findings regarding hallucinogenic and dissociative anesthetic drug-induced discriminative stimulus properties in animals.

Therapeutic Applications of Classic Hallucinogens

This chapter reviews what is known about the therapeutic uses of the serotonergic or classic hallucinogens, i.e., psychoactive drugs such as LSD and psilocybin that exert their effects primarily through agonist activity at serotonin 2A (5HT2A) receptors. Following a review of the history of human use and scientific study of these drugs, the data from clinical research are summarized, including extensive work on the use of classic hallucinogens in the treatment of alcoholism and other addictions, studies of the use of LSD and psilocybin to relieve distress concerning death, particularly in patients with advanced or terminal cancer, and more limited data concerning the use of classic hallucinogens to treat mood and anxiety disorders. A survey of possible mechanisms of clinically relevant effects is provided. The well-established safety of classic hallucinogens is reviewed. To provide a clinical perspective, case summaries are provided of two individuals who received treatment in recent controlled trials of psilocybin: one being treated for alcoholism, the other suffering from anxiety and depression related to fear of death due to a cancer diagnosis. Although promising early phase research conducted from the 1950s through the early 1970s was discontinued before firm conclusions could be reached concerning the efficacy of any of the classic hallucinogens for any clinical condition, the research that was conducted in that era strongly suggests that classic hallucinogens have clinically relevant effects, particularly in the case of LSD treatment of alcoholism. In the past decade, clinical trials have resumed investigating the effects of classic hallucinogens in the treatment of existential distress in the face of cancer, and in the treatment of addictions including alcoholism and nicotine addiction. The studies that have been completed to date are not sufficient to establish efficacy, but the outcomes have been very encouraging, and larger trials, up to and including phase 3, are now underway or being planned. Although research has elucidated many of the acute neurobiological and psychological effects of classic hallucinogens on humans, animals, and in vitro systems, the mechanisms of clinically relevant persisting effects remain poorly understood.

Phenomenology, Structure, and Dynamic of Psychedelic States

Classic serotonergic hallucinogens or psychedelics produce an altered states of consciousness (ASC) that is characterized by profound alterations in sensory perception, mood, thought including the perception of reality, and the sense of self. Over the past years, there has been considerable progress in the search for invariant and common features of psychedelic states. In the first part of this review, we outline contemporary approaches to characterize the structure of ASCs by means of three primary etiology-independent dimensions including oceanic boundlessness, anxious ego-dissolution, and visionary restructuralization as well as by 11 lower-order factors, all of which can be reliably measured by the altered state of consciousness questionnaire (APZ-OAV). The second part sheds light on the dynamic nature of psychedelic experiences. Frequently, psychedelic subjects progress through different stages over time and levels of changes along a perception-hallucination continuum of increasing arousal and ego-dissolution. We then review in detail the acute effects of psychedelics on sensory perception, emotion, cognition, creativity, and time perception along with possible neural mechanisms underlying them. The next part of this review outlines the influence of non-pharmacological factors (predictors) on the acute psychedelic experience, such as demographics, genetics, personality, mood, and setting, and also discusses some long-term effects succeeding the acute experience. The last part presents some recent concepts and models attempting to understand different facets of psychedelic states of consciousness from a neuroscientific perspective.

TCB-2 [(7R)-3-bromo-2, 5-dimethoxy-bicyclo[4.2.0]octa-1,3,5-trien-7-yl]methanamine]: A hallucinogenic drug, a selective 5-HT2A receptor pharmacological tool, or none of the above?

The development of 5-HT_2A receptor agonists has been considerably marginalized since the demonstration that the tryptaminergic drugs, LSD and psilocybin, or the phenylakylamine drugs, mescaline and DOI, exert their hallucinogenic properties via the stimulation of 5-HT_2A receptors. Nonetheless, the ability of drugs to stimulate 5-HT_2A receptors is not necessarily associated with psychedelic experience and the hallucinogenic properties are still not understood. Several studies have increased interest in stimulating 5-HT_2A receptors in various CNS diseases. (7R)-3-bromo-2, 5-dimethoxy-bicyclo[4.2.0]octa-1,3,5-trien-7-yl]methanamine (TCB-2) which was synthetized in 2006 presents a high affinity with human and rat 5-HT_2A receptors. Its main feature of interest is that it preferentially stimulates the phospholipase C and not phospholipase A2 pathway, which is at variance with several hallucinogenic drugs. Preference for TCB-2 has increased in preclinical studies and it exhibits subtle differences compared to DOI or LSD in some molecular, cellular and behavioral studies. The purpose of this review is to take a position on the use of TCB-2 as a pharmacological tool. A careful reading of the literature has revealed that the suspected hallucinogenic properties of TCB-2 cannot firmly be ascertained while its pharmacological profile is unknown and likely not selective at 5-HT_2A receptors. This article is part of the Special Issue entitled 'Psychedelics: New Doors, Altered Perceptions'.

Hallucinogens in Drug Discrimination

Hallucinogens comprise a diverse collection of chemicals with multifarious receptor actions in the central nervous system. Preclinical drug screening methods have proven invaluable in the evaluation and characterization of hallucinogen psychopharmacology. Used in concert with structural chemistry and receptor pharmacology methods, preclinical drug discrimination research has informed our current understanding of hallucinogens and the neurochemical receptor mechanisms responsible for their interoceptive stimulus effects. This chapter summarizes the strengths and limitations of drug discrimination as an in vivo drug detection method and offers a brief review of historical and contemporary drug discrimination research with classical hallucinogens.

The serotonin 5-HT2C receptor and the non-addictive nature of classic hallucinogens

Classic hallucinogens share pharmacology as serotonin 5-HT_2A, 5-HT_2B, and 5-HT_2C receptor agonists. Unique among most other Schedule 1 drugs, they are generally non-addictive and can be effective tools in the treatment of addiction. Mechanisms underlying these attributes are largely unknown. However, many preclinical studies show that 5-HT_2C agonists counteract the addictive effects of drugs from several classes, suggesting this pharmacological property of classic hallucinogens may be significant. Drawing from a comprehensive analysis of preclinical behavior, neuroanatomy, and neurochemistry studies, this review builds rationale for this hypothesis, and also proposes a testable, neurobiological framework. 5-HT_2C agonists work, in part, by modulating dopamine neuron activity in the ventral tegmental area-nucleus accumbens (NAc) reward pathway. We argue that activation of 5-HT_2C receptors on NAc shell, GABAergic, medium spiny neurons inhibits potassium Kv1.x channels, thereby enhancing inhibitory activity via intrinsic mechanisms. Together with experiments that show that addictive drugs, such as cocaine, potentiate Kv1.x channels, thereby suppressing NAc shell GABAergic activity, this hypothesis provides a mechanism by which classic hallucinogen-mediated stimulation of 5-HT_2C receptors could thwart addiction. It also provides a potential reason for the non-addictive nature of classic hallucinogens.

NPS: Medical Consequences Associated with Their Intake

Over the last decade, the 'traditional' drug scene has been supplemented - but not replaced - by the emergence of a range of novel psychoactive substances (NPS), which are either newly created or existing drugs, including medications, now being used in novel ways. By the end of 2014, in excess of 500 NPS had been reported by a large number of countries in the world. Most recent data show, however, that synthetic cathinones, synthetic cannabinoids, and psychedelics/phenethylamines account for the largest number of NPS.The present chapter aims at providing an overview of the clinical and pharmacological issues relating to these most popular NPS categories. Given the vast range of medical and psychopathological issues associated with the molecules here described, it is crucial for health professionals to be aware of the effects and toxicity of NPS. A general overview of the acute management of NPS adverse events is provided as well, although further studies are required to identify a range of evidence-based, index molecule-focused, treatment strategies. The rapid pace of change in the NPS online market constitutes a major challenge to the provision of current and reliable scientific knowledge on these substances.

The current state of research on ayahuasca: A systematic review of human studies assessing psychiatric symptoms, neuropsychological functioning, and neuroimaging

RATIONALE

In recent decades, the use of ayahuasca (AYA) - a β-carboline- and dimethyltryptamine-rich hallucinogenic botanical preparation traditionally used by Northwestern Amazonian tribes for ritual and therapeutic purposes - has spread from South America to Europe and the USA, raising concerns about its possible toxicity and hopes of its therapeutic potential. Thus, it is important to analyze the acute, subacute, and long-term effects of AYA to assess its safety and toxicity.

OBJECTIVES

The purpose of this study was to conduct a systematic review of human studies assessing AYA effects on psychiatric symptoms, neuropsychological functioning, and neuroimaging.

METHODS

Papers published until 16 December 2015 were included from PubMed, LILACS and SciELO databases following a comprehensive search strategy and pre-determined set of criteria for article selection.

RESULTS

The review included 28 full-text articles. Acute AYA administration was well tolerated, increased introspection and positive mood, altered visual perceptions, activated frontal and paralimbic regions and decreased default mode network activity. It also improved planning and inhibitory control and impaired working memory, and showed antidepressive and antiaddictive potentials. Long-term AYA use was associated with increased cortical thickness of the anterior cingulate cortex and cortical thinning of the posterior cingulate cortex, which was inversely correlated to age of onset, intensity of prior AYA use, and spirituality. Subacute and long-term AYA use was not associated with increased psychopathology or cognitive deficits, being associated with enhanced mood and cognition, increased spirituality, and reduced impulsivity.

CONCLUSIONS

Acute, subacute, and long-term AYA use seems to have low toxicity. Preliminary studies about potential therapeutic effects of AYA need replication due to their methodological limitations.

Classical hallucinogens and neuroimaging: A systematic review of human studies: Hallucinogens and neuroimaging

Serotonergic hallucinogens produce alterations of perceptions, mood, and cognition, and have anxiolytic, antidepressant, and antiaddictive properties. These drugs act as agonists of frontocortical 5-HT_2A receptors, but the neural basis of their effects are not well understood. Thus, we conducted a systematic review of neuroimaging studies analyzing the effects of serotonergic hallucinogens in man. Studies published in the PubMed, Lilacs, and SciELO databases until 12 April 2016 were included using the following keywords: "ayahuasca", "DMT", "psilocybin", "LSD", "mescaline" crossed one by one with the terms "mri", "fmri", "pet", "spect", "imaging" and "neuroimaging". Of 279 studies identified, 25 were included. Acute effects included excitation of frontolateral/frontomedial cortex, medial temporal lobe, and occipital cortex, and inhibition of the default mode network. Long-term use was associated with thinning of the posterior cingulate cortex, thickening of the anterior cingulate cortex, and decreased neocortical 5-HT_2A receptor binding. Despite the high methodological heterogeneity and the small sample sizes, the results suggest that hallucinogens increase introspection and positive mood by modulating brain activity in the fronto-temporo-parieto-occipital cortex.

Psychosis associated with acute recreational drug toxicity: a European case series

BACKGROUND

Psychosis can be associated with acute recreational drug and novel psychoactive substance (NPS) toxicity. However, there is limited data available on how common this is and which drugs are most frequently implicated. We describe a European case series of psychosis associated with acute recreational drug toxicity, and estimate the frequency of psychosis for different recreational drugs.

METHODS

The European Drug Emergencies Network (Euro-DEN) collects data on presentations to Emergency Departments (EDs) with acute recreational drug and NPS toxicity at 16 centres in ten countries. Euro-DEN data from October 2013 through September 2014 was retrospectively searched, and cases with psychosis were included. The proportion of cases with psychosis per drug was calculated in the searched Euro-DEN dataset.

RESULTS

Psychosis was present in 348 (6.3 %) of 5529 cases. The median (interquartile range) age was 29 (24-38) years, 276 (79.3 %) were male and 114 (32.8 %) were admitted to psychiatric ward. The drugs most commonly reported were cannabis in 90 (25.9 %) cases, amphetamine in 87 (25.0 %) and cocaine in 56 (16.1 %). More than one drug was taken in 189 (54.3 %) cases. Psychosis was frequent in those ED presentations involving tryptamines (4/7; 57.1 %), methylenedioxypyrovalerone (MDPV) (6/22; 27.3 %), methylphenidate (6/26; 23.1 %), lysergic acid diethylamide (LSD) (18/86; 20.9 %), psilocybe mushrooms (3/16; 18.8 %), synthetic cannabinoid receptor agonists (4/26; 15.4 %) and amphetamine (87/593; 14.7 %), but less common in those involving mephedrone (14/245; 5.7 %), methylenedioxymethamphetamine (MDMA) (20/461; 4.3 %) and methedrone (3/92; 3.3 %). Amphetamine was the most frequent drug associated with psychosis when only one agent was reported, with psychosis occurring in 32.4 % of these presentations.

CONCLUSION

The frequency of psychosis in acute recreational drug toxicity varies considerably between drugs, but is a major problem in amphetamine poisoning. In rapidly changing drug markets and patterns of use, the Euro-DEN sentinel network contributes to measuring the scale of drug-related harms in Europe beyond other more established indicators.

Receptor interaction profiles of novel psychoactive tryptamines compared with classic hallucinogens

The present study investigated interactions between the novel psychoactive tryptamines DiPT, 4-OH-DiPT, 4-OH-MET, 5-MeO-AMT, and 5-MeO-MiPT at monoamine receptors and transporters compared with the classic hallucinogens lysergic acid diethylamide (LSD), psilocin, N,N-dimethyltryptamine (DMT), and mescaline. We investigated binding affinities at human monoamine receptors and determined functional serotonin (5-hydroxytryptamine [5-HT]) 5-HT2A and 5-HT2B receptor activation. Binding at and the inhibition of human monoamine uptake transporters and transporter-mediated monoamine release were also determined. All of the novel tryptamines interacted with 5-HT2A receptors and were partial or full 5-HT2A agonists. Binding affinity to the 5-HT2A receptor was lower for all of the tryptamines, including psilocin and DMT, compared with LSD and correlated with the reported psychoactive doses in humans. Several tryptamines, including psilocin, DMT, DiPT, 4-OH-DiPT, and 4-OH-MET, interacted with the serotonin transporter and partially the norepinephrine transporter, similar to 3,4-methylenedioxymethamphetamine but in contrast to LSD and mescaline. LSD but not the tryptamines interacted with adrenergic and dopaminergic receptors. In conclusion, the receptor interaction profiles of the tryptamines predict hallucinogenic effects that are similar to classic serotonergic hallucinogens but also MDMA-like psychoactive properties.

Abuse potential of methylenedioxymethamphetamine (MDMA) and its derivatives in zebrafish: role of serotonin 5HT2-type receptors

RATIONALE

The synthetic phenethylamines are recreational drugs known to produce psychostimulant effects. However, their abuse potential has not been widely studied.

OBJECTIVES

Here, we investigated the rewarding and the hallucinatory effects of 2,5-dimetoxy-4-bromo-amphetamine hydrobromide (DOB) and para-methoxyamphetamine (PMA) in comparison with the classical 3,4-methylenedioxymethamphetamine (MDMA). In addition, the role of serotonin 5-HT2-like receptor on the abovementioned effects was evaluated.

METHODS

Zebrafish were intramuscularly (i.m.) treated with a wide range of doses of DOB (0.1-20 mg/kg), PMA (0.0005-2 mg/kg), or MDMA (0.5-160 mg/kg). Animals were submitted to a conditioned place preference (CPP) task, to investigation of the rewarding properties, and to the evaluation of hallucinatory behavior in terms of appearance of a trance-like behavior. The serotonin 5-HT2 subtype receptor antagonist ritanserin (0.025-2.5 mg/kg) in association with the maximal effective dose of MDMA, DOB, and PMA was given i.m., and the effect on CPP or hallucinatory behavior was evaluated.

RESULTS

MDMA and its derivatives exhibited CPP in a biphasic fashion, being PMA the most potent. This effect was accompanied, for DOB (2 mg/kg) and PMA (0.1 mg/kg), by a trance-like hallucinatory behavior. MDMA at a high dose as 160 mg/kg did not induce any hallucinatory behavior. Ritanserin significantly blocked the rewarding and hallucinatory effects suggesting the involvement of serotonin 5HT2 subtype receptor.

CONCLUSION

Collectively, these findings demonstrate for the first time that the rewarding properties of DOB and PMA are accompanied by hallucinatory behavior through a serotonergic system and reinforce zebrafish as an emerging experimental model for screening new hallucinogens.

Hallucinogen use and intimate partner violence: Prospective evidence consistent with protective effects among men with histories of problematic substance use

Evidence suggests that hallucinogens may have therapeutic potential for addressing a variety of problem behaviors related to the externalizing spectrum of psychopathology, such as substance misuse and criminality. Intimate partner violence (IPV) is a prevalent form of criminal violence that is related to externalizing pathology. However, the association between hallucinogen use and IPV has not been comprehensively examined. In this prospective study, we examined the association between IPV and naturalistic hallucinogen use among 302 inmates at a US county jail. Cox regression analyses indicated that hallucinogen use predicted reduced arrest for IPV independently (β=-0.54, SE=0.20, χ(2)=7.19, exp(B)=0.58, p<0.01) and after accounting for covariates (β=-0.48, SE=0.23, χ(2)=4.44, exp(B)=0.62, p<0.05). These results add to a growing literature suggesting distinct therapeutic potential for hallucinogens to assist in the attenuation of problematic behavior.

[Factors Related With Psychoactive Substance Use in an Educational Institution in Jamundí Valle, Colombia]

OBJECTIVE

To estimate the prevalence of psychoactive substances (SPA) use in young people in an educational institution in Jamundí and possible related factors.

METHODS

Cross-sectional study, analytical approach that simulates cases and controls, was conducted in an educational institution in Jamundí-Valley. The sample was composed of 146 students selected through simple random probability sampling without replacement. Participants individually and anonymously completed a questionnaire to identify SPA consumption and associated factors, including APGAR scale to measure family functioning. The data extracted from the questionnaires were entered into a matrix in Microsoft Excel and processed in EpiInfo version 5.0 and Stata. Descriptive analysis was performed, and a multivariate analysis was performed using unconditional logistic regression.

RESULTS

Current consumption of SPA, 35%; age of first use was 10 to 13 years; the prevalence of drug misuse by gender was 34% for girls and 37% in boys. The most consumed legal substance was alcohol 34%, and illegal 3%. The most significant associations with the use of psychoactive substances was; having severe family dysfunction (OR=7.32; 95%CI, 1.74-30.76), being enrolled in the 11th grade (OR=14.6; 95%CI, 2.37-89.74), and having friends who use (OR=3.12; 95%CI, 2.49-10.38).

CONCLUSIONS

The results obtained in this study show a high percentage of SPA consumption, with a higher prevalence in males. In this population, the most commonly used legal substance is alcohol. Family dysfunction and school grade were significantly associated with drug misuse.

Effects of LSD on grooming behavior in serotonin transporter heterozygous (Sert⁺/⁻) mice

Serotonin (5-HT) plays a crucial role in the brain, modulating mood, cognition and reward. The serotonin transporter (SERT) is responsible for the reuptake of 5-HT from the synaptic cleft and regulates serotonin signaling in the brain. In humans, SERT genetic variance is linked to the pathogenesis of various psychiatric disorders, including anxiety, autism spectrum disorders (ASD) and obsessive-compulsive disorder (OCD). Rodent self-grooming is a complex, evolutionarily conserved patterned behavior relevant to stress, ASD and OCD. Genetic ablation of mouse Sert causes various behavioral deficits, including increased anxiety and grooming behavior. The hallucinogenic drug lysergic acid diethylamide (LSD) is a potent serotonergic agonist known to modulate human and animal behavior. Here, we examined heterozygous Sert(+/-) mouse behavior following acute administration of LSD (0.32 mg/kg). Overall, Sert(+/-) mice displayed a longer duration of self-grooming behavior regardless of LSD treatment. In contrast, LSD increased serotonin-sensitive behaviors, such as head twitching, tremors and backwards gait behaviors in both Sert(+/+) and Sert(+/-) mice. There were no significant interactions between LSD treatment and Sert gene dosage in any of the behavioral domains measured. These results suggest that Sert(+/-) mice may respond to the behavioral effects of LSD in a similar manner to wild-type mice.

Receptor interaction profiles of novel N-2-methoxybenzyl (NBOMe) derivatives of 2,5-dimethoxy-substituted phenethylamines (2C drugs)

BACKGROUND

N-2-methoxybenzyl-phenethylamines (NBOMe drugs) are newly used psychoactive substances with poorly defined pharmacological properties. The aim of the present study was to characterize the receptor binding profiles of a series of NBOMe drugs compared with their 2,5-dimethoxy-phenethylamine analogs (2C drugs) and lysergic acid diethylamide (LSD) in vitro.

METHODS

We investigated the binding affinities of 2C drugs (2C-B, 2C-C, 2C-D, 2C-E, 2C-H, 2C-I, 2C-N, 2C-P, 2C-T-2, 2C-T-4, 2C-T-7, and mescaline), their NBOMe analogs, and LSD at monoamine receptors and determined functional 5-hydroxytryptamine-2A (5-HT2A) and 5-HT2B receptor activation. Binding at and the inhibition of monoamine uptake transporters were also determined. Human cells that were transfected with the respective human receptors or transporters were used (with the exception of trace amine-associated receptor-1 [TAAR1], in which rat/mouse receptors were used).

RESULTS

All of the compounds potently interacted with serotonergic 5-HT2A, 5-HT2B, 5-HT2C receptors and rat TAAR1 (most Ki and EC50: <1 μM). The N-2-methoxybenzyl substitution of 2C drugs increased the binding affinity at serotonergic 5-HT2A, 5-HT2C, adrenergic α1, dopaminergic D1-3, and histaminergic H1 receptors and monoamine transporters but reduced binding to 5-HT1A receptors and TAAR1. As a result, NBOMe drugs were very potent 5-HT2A receptor agonists (EC50: 0.04-0.5 μM) with high 5-HT2A/5-HT1A selectivity and affinity for adrenergic α1 receptors (Ki: 0.3-0.9 μM) and TAAR1 (Ki: 0.06-2.2 μM), similar to LSD, but not dopaminergic D1-3 receptors (most Ki:>1 μM), unlike LSD.

CONCLUSION

The binding profile of NBOMe drugs predicts strong hallucinogenic effects, similar to LSD, but possibly more stimulant properties because of α1 receptor interactions.

Peak experiences and the afterglow phenomenon: when and how do therapeutic effects of hallucinogens depend on psychedelic experiences?

Interest in the therapeutic potential of psychedelic substances has recently resumed. During an early phase of human psychedelic research, their therapeutic application in different pathologies had been suggested, and the first evidence for efficacy was provided. The range of recent clinical applications of psychedelics spans from cluster headaches and obsessive-compulsive disorder to addiction and the treatment of fear and anxiety in patients suffering from terminal illness, indicating potentially different therapeutic mechanisms. A variety of approaches in psychotherapy emphasize subjective experiences, such as so-called peak experiences or afterglow phenomena, as differentially mediating therapeutic action. This review aims to re-evaluate earlier and recent concepts of how psychedelic substances may exert beneficial effects. After a short outline of neurophenomenological aspects, we discuss different approaches to how psychedelics are used in psychotherapy. Finally, we summarize evidence for the relationship between subjective experiences and therapeutic success. While the distinction between pharmacological and psychological action obviously cannot be clear-cut, they do appear to contribute differently from each other when their effects are compared with regard to pathologies.

Determination of muscimol and ibotenic acid in mushrooms of Amanitaceae by capillary electrophoresis

In this study, the CZE method for rapid quantitative and qualitative determination of ibotenic acid and muscimol in Amanita mushrooms naturally grown in Poland was developed. The investigations included the species of A. muscaria, A. pantherina, and A. citrina, collected in southern region of Poland. The studied hallucinogenic compounds were effectively extracted with a mixture of methanol and 1 mM sodium phosphate buffer at pH 3 (1:1 v/v) using ultrasound-assisted procedure. The obtained extracts were separated and determined by CZE utilizing a 25 mM sodium phosphate running buffer adjusted to pH 3 with 5% content of acetonitrile v/v. The calibration curves for both analytes were linear in the range of 2.5-7000 μg/mL. The intraday and interday variations of quantitative data were 1.0 and 2.5% RSD, respectively. The recovery values of analyzed compounds were over 87%. The identities of ibotenic acid and muscimol were confirmed by UV spectra, migration time, and measurements after addition of external standard.

Psilocybin--summary of knowledge and new perspectives

Psilocybin, a psychoactive alkaloid contained in hallucinogenic mushrooms, is nowadays given a lot of attention in the scientific community as a research tool for modeling psychosis as well as due to its potential therapeutic effects. However, it is also a very popular and frequently abused natural hallucinogen. This review summarizes all the past and recent knowledge on psilocybin. It briefly deals with its history, discusses the pharmacokinetics and pharmacodynamics, and compares its action in humans and animals. It attempts to describe the mechanism of psychedelic effects and objectify its action using modern imaging and psychometric methods. Finally, it describes its therapeutic and abuse potential.

Psychoactive substances--some new, some old: a scan of the situation in the U.S

New synthetic drugs are appearing as old hallucinogen psychedelic drugs are reappearing. This article combines the findings from a variety of datasets to characterize the users in terms of gender, age, drug use patterns, and adverse results, as well as provide an overview of the changes in formulations of these drugs and the impact of legal controls. Methods. Data from Monitoring the Future and the National Survey on Drug Use and Health are analyzed, along with the national DAWN emergency room admissions, Texas poison control center cases, and Texas treatment data, along with national forensic laboratory results. Results. Users of the synthetic cannabinoids, synthetic cathinones, phenethylamines, tryptamines, LSD, MDMA, and mushrooms tended to be young and male. They differed in terms of race and ethnicity. The effects of the drugs differed in terms of emergency room outcomes and poison center reports, and the treatment data showed they were similar in terms of education level, employment, and legal problems. Conclusion. Combining the different data sources provided a first picture of the characteristics of these users and their needs. Creditable descriptions on the risks of these drugs should be disseminated. Intervention programs should be targeted to these young users and new neuropsychobiological deficits from some of these drugs should be monitored. Because of the ever-changing chemical combinations to stay legal and the need for information on content and dosage, a more effective approach may be needed basing control on the effects of the substances rather than their changing chemical composition.