Potential Therapeutic Effects of Psilocybin

Behavioral arrest and a characteristic slow waveform are hallmark responses to selective 5-HT2A receptor activation

Perception, emotion, and mood are powerfully modulated by serotonin receptor (5-HTR) agonists including hallucinogens. The 5-HT_2AR subtype has been shown to be central to hallucinogen action, yet the precise mechanisms mediating the response to 5-HT_2AR activation remain unclear. Hallucinogens induce the head twitch response (HTR) in rodents, which is the most commonly used behavioral readout of hallucinogen pharmacology. While the HTR provides a key behavioral signature, less is known about the meso level changes that are induced by 5-HT_2AR activation. In response to administration of the potent and highly selective 5-HT_2AR agonist 25I-NBOH in mice, we observe a disorganization of behavior which includes frequent episodes of behavioral arrest that consistently precede the HTR by a precise interval. By combining behavioral analysis with electroencephalogram (EEG) recordings we describe a characteristic pattern composed of two distinctive EEG waveforms, Phase 1 and Phase 2, that map onto behavioral arrest and the HTR respectively, with the same temporal separation. Phase 1, which underlies behavioral arrest, is a 3.5-4.5 Hz waveform, while Phase 2 is slower at 2.5-3.2 Hz. Nicotine pretreatment, considered an integral component of ritualistic hallucinogen practices, attenuates 25I-NBOH induced HTR and Phase 2 waveforms, yet increases behavioral arrest and Phase 1 waveforms. Our results suggest that in addition to the HTR, behavioral arrest and characteristic meso level slow waveforms are key hallmarks of the response to 5-HT_2AR activation. Increased understanding of the response to serotonergic hallucinogens may provide mechanistic insights into perception and hallucinations, as well as regulation of mood.

Increases in Psychological Flexibility Mediate Relationship Between Acute Psychedelic Effects and Decreases in Racial Trauma Symptoms Among People of Color

BACKGROUND

Previous research showed acute psychedelic effects were associated with decreases in racial trauma (RT) symptoms among black, indigenous, and people of color (BIPOC). Among samples comprised primarily of white participants, positive outcomes of psychedelic experiences have been mediated by increases in psychological flexibility. Therefore, we examined whether changes in psychological flexibility from before to after a psychedelic experience mediated the relationship between acute psychedelic effects and changes in RT symptoms among BIPOC.

METHODS

This cross-sectional online survey study included 313 BIPOC (mean age = 33.1; SD = 11.2; female = 57%). A multiple linear regression analysis was used to examine the association between acute psychedelic effects and decreases in RT symptoms in a nonclinical setting; a path analysis was used to explore whether changes in psychological flexibility mediated this relationship.

RESULTS

Acute insight and challenging effects were significantly (p < .001) associated with decreases in RT symptoms following a psychedelic experience. Increases in psychological flexibility partially mediated relationships between greater intensity of psychological insight and less intensity of challenging experiences and decreases in RT symptoms (ps<.001).

CONCLUSION

This research suggests psychedelics confer potential benefits in decreasing RT symptoms among BIPOC and psychological flexibility may be an important mediator of these effects. Future research should test this hypothesis in a longitudinal clinical trial among BIPOC.

People of color in North America report improvements in racial trauma and mental health symptoms following psychedelic experiences

This study examined how psychedelics reduced symptoms of racial trauma among black, indigenous, and people of color (BIPOC) subsequent to an experience of racism. A cross-sectional internet-based survey included questions about experiences with racism, mental health symptoms, and acute and enduring psychedelic effects. Changes in mental health were assessed by retrospective report of symptoms in the 30 days before and 30 days after an experience with psilocybin, Lysergic acid diethylamide (LSD), or 3,4-Methylenedioxymethamphetamine (MDMA). We recruited 313 diverse BIPOC in the US and Canada. Results revealed a significant (p < .001) and moderate (d = −.45) reduction in traumatic stress symptoms from before-to-after the psychedelic experience. Similarly, participants reported decreases in depression (p < .001; d = −.52), anxiety (p < .001; d = −.53), and stress (p < .001; d = −.32). There was also a significant relationship (R_c = 0.52, p < .001) between the dimension of acute psychedelic effects (mystical-type, insight, and challenging experiences) and decreases in a cluster of subsequent psychopathology (traumatic stress, depression, anxiety, and stress), while controlling for the frequency of prior discrimination and the time since the psychedelic experience. BIPOC have been underrepresented in psychedelic studies. Psychedelics may decrease the negative impact of racial trauma. Future studies should examine the efficacy of psychedelic-assisted therapy for individuals with a history of race-based trauma.

Virtual Reality and Psychedelics for the Treatment of Psychiatric Disease: A Systematic Literature Review

OBJECTIVE

Hallucinogenic substances or psychedelic drugs have been historically used by humans worldwide for centuries, and interest grows around them because of the therapeutic potential that they pose for mental disease. Virtual Reality (VR), has been highly developed and improved in the last decade, and it is also gaining importance due to their potential as therapeutic tools. In this article, the most recent and relevant information regarding the medical applications of both VR and psychedelics was highlighted, and diverse potential therapeutic uses were explored in hope to set the ground for further research on this topic.

METHOD

A systematic literature review using the PRISMA methods was conducted in PubMed, Medline, Embase, Cochrane Library, Scopus and Web of Science, including only peer-reviewed clinical trials or case studies written in English, that address the use of psychedelics and/or VR for the treatment of psychiatric disorders and that measure the success of the therapies. A final selection of 23 manuscripts were used in this systematic review.

RESULTS

VR showed security and significant efficacy in the management of special cases of phobias (social, motion pain and spiders), eating disorder, post-traumatic stress disorder (PTSD), gambling disorder, preoperative anxiety and schizophrenia.

CONCLUSIONS

The hallucinogenic drugs evaluated exhibited positive effects in treatment of depressive and anxiety disorders, alcohol dependence and PTSD. More research is needed in order to test the effectiveness of these therapies (alone or together) in different mental illnesses and different populations.

Psychedelics as an emerging novel intervention in the treatment of substance use disorder: a review

Classical psychedelics are a group of drugs characterized by their activation of the serotonin-2A (5-hydroxytryptamine-2A; 5-HT2A) receptor and the unique hallucinogenic and mystical-type experiences that result. After a substantial period of restrictions limiting investigations into the therapeutic potential of psychedelics, a relatively recent recommencement of interest has sparked the burgeoning possibility for these drugs to play a part in the treatment of a wide array of psychopathologies. One of the most promising is in the study of addiction. Evidence has emerged that psychedelic agents may provide a novel avenue for the clinical treatment of patients dealing with substance use disorders (SUD). These serotonergic hallucinogens have displayed remarkable and enduring positive outcomes in this area, even when administered as one or two doses. The neural targets for these psychedelics are varied and underlie a complex mechanism of action-modulating multiple neural networks. It is believed that these agents allow for the reorganization of disordered neural pathways in the default mode network and attenuate maladaptive signaling in mesolimbic reward circuitry. The aim of this review is to examine the current standing of evidence regarding psychedelic psychopharmacology and to provide an overview of the use and effectiveness of these drugs in the treatment of SUD, alcohol use disorder, and for smoking cessation.

[Ketamine, psilocybin, and rapid acting antidepressant: new promise for psychiatry?]

The hypothesis of monoaminergic deficiency has long dominated the conceptual framework for the development of new antidepressant strategies, but the limits of conventional antidepressant treatments targeting monoaminergic signaling have motivated the search for new antidepressant pathways. The success of ketamine in the management of depressive disorders has provoked a renewed interest in hallucinogenic substances such as psilocybin targeting the serotonergic signaling 5HT^2A and neurosteroid allosteric modulator of γ-aminobutyric acid (GABAA) receptors such as brexanolone. Unlike conventional treatments, these modulators of glutamatergic, serotonergic and GABAergic systems exert a rapid antidepressant effect ranging from 24hours to a week. Apart from their clinical interest and the fantasized search for a "miracle" molecule that jointly meets the expectations of patients and clinicians, these new targets could lead to the identification of potential new biomarkers for the development of rapid-acting antidepressants and redefine therapeutic strategies in mood disorders.

The hydro-chloride salt of 4-hy-droxy-N,N-di-n-propyl-tryptamine (4-HO-DPT)

The title compound, 4-hy-droxy-N,N-di-n-propyl-tryptammonium (4-HO-DPT) chloride {systematic name: N-[2-(4-hy-droxy-1H-indol-3-yl)eth-yl]-N-propyl-propan-1-aminium chloride}, C16H25N2O+·Cl-, has a singly protonated trypt-ammonium cation and one chloride anion in the asymmetric unit. A series of N-H⋯Cl and O-H⋯Cl hydrogen bonds connect the ions together in ladder chains along [010].

Psychedelic Treatments for Psychiatric Disorders: A Systematic Review and Thematic Synthesis of Patient Experiences in Qualitative Studies

INTRODUCTION

Interest in the use of psychedelic substances for the treatment of mental disorders is increasing. Processes that may affect therapeutic change are not yet fully understood. Qualitative research methods are increasingly used to examine patient accounts; however, currently, no systematic review exists that synthesizes these findings in relation to the use of psychedelics for the treatment of mental disorders.

OBJECTIVE

To provide an overview of salient themes in patient experiences of psychedelic treatments for mental disorders, presenting both common and diverging elements in patients' accounts, and elucidating how these affect the treatment process.

METHODS

We systematically searched the PubMed, MEDLINE, PsycINFO, and Embase databases for English-language qualitative literature without time limitations. Inclusion criteria were qualitative research design; peer-reviewed studies; based on verbalized patient utterances; and a level of abstraction or analysis of the results. Thematic synthesis was used to analyze and synthesize results across studies. A critical appraisal of study quality and methodological rigor was conducted using the Critical Appraisal Skills Programme (CASP).

RESULTS

Fifteen research articles, comprising 178 patient experiences, were included. Studies exhibited a broad heterogeneity in terms of substance, mental disorder, treatment context, and qualitative methodology. Substances included psilocybin, lysergic acid diethylamide (LSD), ibogaine, ayahuasca, ketamine and 3,4-methylenedioxymethamphetamine (MDMA). Disorders included anxiety, depression, eating disorders, post-traumatic stress disorder, and substance use disorders. While the included compounds were heterogeneous in pharmacology and treatment contexts, patients reported largely comparable experiences across disorders, which included phenomenological analogous effects, perspectives on the intervention, therapeutic processes and treatment outcomes. Comparable therapeutic processes included insights, altered self-perception, increased connectedness, transcendental experiences, and an expanded emotional spectrum, which patients reported contributed to clinically and personally relevant responses.

CONCLUSIONS

This review demonstrates how qualitative research of psychedelic treatments can contribute to distinguishing specific features of specific substances, and carry otherwise undiscovered implications for the treatment of specific psychiatric disorders.

Compassionate use of psychedelics

In the present paper, we discuss the ethics of compassionate psychedelic psychotherapy and argue that it can be morally permissible. When talking about psychedelics, we mean specifically two substances: psilocybin and MDMA. When administered under supportive conditions and in conjunction with psychotherapy, therapies assisted by these substances show promising results. However, given the publicly controversial nature of psychedelics, compassionate psychedelic psychotherapy calls for ethical justification. We thus review the safety and efficacy of psilocybin- and MDMA-assisted therapies and claim that it can be rational for some patients to try psychedelic therapy. We think it can be rational despite the uncertainty of outcomes associated with compassionate use as an unproven treatment regime, as the expected value of psychedelic psychotherapy can be assessed and can outweigh the expected value of routine care, palliative care, or no care at all. Furthermore, we respond to the objection that psychedelic psychotherapy is morally impermissible because it is epistemically harmful. We argue that given the current level of understanding of psychedelics, this objection is unsubstantiated for a number of reasons, but mainly because there is no experimental evidence to suggest that epistemic harm actually takes place.

Phytochemical, Cytotoxicity, Antioxidant and Anti-Inflammatory Effects of Psilocybe Natalensis Magic Mushroom

Psilocybin-containing mushrooms, commonly known as magic mushrooms, have been used since ancient and recent times for depression and to improve quality of life. However, their anti-inflammatory properties are not known. The study aims at investing cytotoxicity; antioxidant; and, for the first time, anti-inflammatory effects of Psilocybe natalensis, a psilocybin-containing mushroom that grows in South Africa, on lipopolysaccharide-induced RAW 264.7 macrophages. Macrophage cells were stimulated with lipopolysaccharide and treated with different concentrations of Psilocybe natalensis mushroom extracted with boiling hot water, cold water and ethanol over 24 h. Quercetin and N-nitro-L-arginine methyl ester were used as positive controls. Effects of extracts on the lipopolysaccharide-induced nitric oxide, prostaglandin E₂, and cytokine activities were investigated. Phytochemical analysis, and the antioxidant and cytotoxicity of extracts, were determined. Results showed that the three extracts inhibited the lipopolysaccharide-induced nitric oxide, prostaglandin E₂, and interleukin 1β cytokine production significantly in a dose-dependent manner close to that of the positive controls. A study proposed that ethanol and water extracts of Psilocybe natalensis mushroom were safe at concentrations used, and have antioxidant and anti-inflammatory effects. Phytochemical analysis confirmed the presence of natural antioxidant and anti-inflammatory compounds in the mushroom extracts.

The therapeutic potential of microdosing psychedelics in depression

Microdosing psychedelics is the repeated use of small doses of, for example, lysergic acid diethylamide (LSD) and psilocybin, typically for a few weeks. Despite the popular and scientific attention in recent years, and claims by users that it has therapeutic value in affective disorders like depression, little scientific knowledge is available to back this. The purpose of this review was to investigate whether there are scientific grounds to state that this practice could be helpful in the treatment of affective disorders, and safe to use repeatedly. To that end, the literature (PubMed, MedLine) was searched, looking for (controlled) experimental studies with low doses of LSD and/or psilocybin, in healthy volunteers and patient samples. After a selection process and the addition of relevant articles, 14 experimental studies entered this review. Findings show that both LSD (10-20 mcg) and psilocybin (<1-3 mg) have subtle (positive) effects on cognitive processes (time perception, convergent and divergent thinking) and brain regions involved in affective processes. Besides the pleasant experience, increased anxiety and a cycling pattern of depressive and euphoric mood were also found. With regard to safety, it was demonstrated that low doses are well tolerated (in healthy volunteers) and have no-to-minimal effects on physiological measures. While it is yet unclear whether psychedelic microdosing is of therapeutic value for depression, the aforementioned effects on selective processes suggest that low doses of psychedelics could play a role in depression by inducing some kind of cognitive flexibility, which might lead to decreased rumination. While previous studies were conducted mostly in small samples of healthy volunteers, future placebo-controlled clinical trials in depressed patients are required to understand the therapeutic value of microdosing psychedelics, how this differs from therapy using full psychedelic doses, and whether different psychedelics have different effect patterns. The proposed research will give new insights into the potential of future alternative psychiatric treatment forms that are fiercely needed.

Quaternary tryptammonium salts: N,N-dimethyl-N-n-propyl-tryptammonium (DMPT) iodide and N-allyl-N,N-di-methyl-tryptammonium (DMALT) iodide

The solid-state structures of two quaternary trytpammonium salts, namely, N,N-dimethyl-N-n-propyl-tryptammonium (DMPT) iodide [systematic name: 2-(1H-indol-3-yl)-N,N-dimethyl-N-propyl-aza-nium iodide], C15H23N2 +·I-, and N-allyl-N,N-di-methyl-tryptammonium (DMALT) iodide, [systematic name: 2-(1H-indol-3-yl)-N,N-dimethyl-N-(prop-2-en-1-yl)aza-nium iodide], C15H21N2 +·I-, are reported. Both salts possess a tri-alkyl-tryptammonium cation and an iodide anion in the asymmetric unit, which are joined together through N-H⋯I inter-actions. The DMALT structure was refined as an inversion twin, and the allyl group is disordered over two orientations with a 0.70 (4):0.30 (4) ratio.

Direct Phosphorylation of Psilocin Enables Optimized cGMP Kilogram-Scale Manufacture of Psilocybin

A second-generation kilogram-scale synthesis of the psychedelic tryptamine psilocybin has been developed. The synthesis was designed to address several challenges first encountered with the scale-up of previously described literature procedures, which were not optimized for providing consistent yield and purity of products, atom economy, or being run in pilot plant-scale reactors. These challenges were addressed and circumvented with the design of the second-generation route, which featured an optimized cGMP large-scale Speeter-Anthony tryptamine synthesis to the intermediate psilocin with improved in-process control and impurity removal over the three steps. Psilocin was subsequently phosphorylated directly with phosphorous oxychloride for the first time, avoiding a tedious and poor atom economy benzyl-protecting group strategy common to all previously described methods for producing psilocybin. In this report, the challenges encountered in a 100 g scale first-generation literature-based synthesis are highlighted, followed by a detailed description of the newly developed second-generation synthesis to provide over one kilogram of high-purity psilocybin under cGMP.

Scalable Hybrid Synthetic/Biocatalytic Route to Psilocybin

Psilocybin, the principal indole alkaloid of Psilocybe mushrooms, is currently undergoing clinical trials as a medication against treatment-resistant depression and major depressive disorder. The psilocybin supply for pharmaceutical purposes is met by synthetic chemistry. We replaced the problematic phosphorylation step during synthesis with the mushroom kinase PsiK. This enzyme was biochemically characterized and used to produce one gram of psilocybin from psilocin within 20 minutes. We also describe a pilot-scale protocol for recombinant PsiK that yielded 150 mg enzyme in active and soluble form. Our work consolidates the simplicity of tryptamine chemistry with the specificity and selectivity of enzymatic catalysis and helps provide access to an important drug at potentially reasonable cost.

Use of Benefit Enhancement Strategies among 5-Methoxy-N,N-Dimethyltryptamine (5-MeO-DMT) Users: Associations with Mystical, Challenging, and Enduring Effects

5-Methoxy-N,N-Dimethyltryptamine (5-MeO-DMT) is a potent, fast-acting psychedelic. Anecdotal reports from 5-MeO-DMT users suggest that they employ a variety of benefit enhancement (BE) strategies aimed to increase positive effects and decrease any potential challenging effects of the substance, but no empirical study has investigated this claim. We examined the prevalence of BE strategy use using secondary data from a survey of 5-MeO-DMT users (n = 515; Mage = 35.4, SD = 11.7; Male = 79%; White/Caucasian = 86%). Results indicated that BE strategy use was common in this sample. As a secondary aim, we assessed whether the use of BE strategies was associated with acute subjective (i.e., mystical-type, challenging) and persisting effects of 5-MeO-DMT among a subset of respondents who reported using 5-MeO-DMT once in their lifetime (n = 116). Results showed that the use of several BE strategies were associated with significantly more intense mystical-type effects and enduring beliefs about the personal meaning and spiritual significance of their experience, and some BE strategies were associated with less intense or challenging experiences. Data suggests that BE strategies are commonly used, and that the use of BE strategies may be associated with increases in positive mystical-type and enduring effects. The causal influence of BE strategies on acute/persisting effects of 5-MeO-DMT should be examined in longitudinal research.

Ethics and ego dissolution: the case of psilocybin

Despite the fact that psychedelics were proscribed from medical research half a century ago, recent, early-phase trials on psychedelics have suggested that they bring novel benefits to patients in the treatment of several mental and substance use disorders. When beneficial, the psychedelic experience is characterized by features unlike those of other psychiatric and medical treatments. These include senses of losing self-importance, ineffable knowledge, feelings of unity and connection with others and encountering 'deep' reality or God. In addition to symptom relief, psychedelic experiences often lead to significant changes in a patient's personality and worldview. Focusing on the case of psilocybin, we argue that the peculiar features of psychedelics pose certain novel risks, which warrant an enhanced informed consent process-one that is more comprehensive than what may be typical for other psychiatric medications. We highlight key issues that should be focused on during the consent process and suggest discussion prompts for enhanced consent in psychedelic psychiatry. Finally, we respond to potential objections before concluding with a discussion of ethical considerations that will arise as psychedelics proceed from highly controlled research environments into mainstream clinical psychiatry.

A Hallucinogenic Serotonin-2A Receptor Agonist Reduces Visual Response Gain and Alters Temporal Dynamics in Mouse V1

Sensory perception arises from the integration of externally and internally driven representations of the world. Disrupted balance of these representations can lead to perceptual deficits and hallucinations. The serotonin-2A receptor (5-HT_2AR) is associated with such perceptual alterations, both in its role in schizophrenia and in the action of hallucinogenic drugs. Despite this powerful influence on perception, relatively little is known about how serotonergic hallucinogens influence sensory processing in the neocortex. Using widefield and two-photon calcium imaging and single-unit electrophysiology in awake mice, we find that administration of the hallucinogenic selective 5-HT_2AR agonist DOI (2,5-dimethoxy-4-iodoamphetamine) leads to a net reduction in visual response amplitude and surround suppression in primary visual cortex, as well as disrupted temporal dynamics. However, basic retinotopic organization, tuning properties, and receptive field structure remain intact. Our results provide support for models of hallucinations in which reduced bottom-up sensory drive is a key factor leading to altered perception.

Activation of serotonin-2A receptors (5-HT_2ARs) is associated with hallucinations, but impacts on sensory processing are largely unknown. Michaiel et al. demonstrate that the 5-HT_2AR agonist DOI strongly reduces sensory-evoked activity and disrupts temporal dynamics. These results support models of hallucinations that propose reduced bottom-up sensory drive.

Exposure-Response Analysis to Assess the Concentration-QTc Relationship of Psilocybin/Psilocin

Psilocybin is being developed for treating major depressive disorder. Psilocybin is readily dephosphorylated to psilocin upon absorption. The potential for psilocin proarrhythmic effect was assessed using a concentration-QTc interval (C-QTc) analysis from an open-label single ascending dose study of psilocybin. Psilocybin doses ranged from 0.3 to 0.6 mg/kg. This trial showed a significant but shallow C-QTc relationship. At the clinical dose of 25 mg, the mean psilocin maximum concentration is 18.7 ng/mL, and the associated mean (upper 90% confidence interval of mean) QTcF change is 2.1 (6.6) milliseconds. Given the short half-life of psilocin of about 4 hours, there would be no accumulation after monthly oral doses used in clinical trials. The upper limit of the 90% confidence interval of the model-predicted mean ΔQTcF crossed 10 milliseconds at a psilocin concentration of 31.1 ng/mL. At a supraclinical psilocin maximum concentration of about 60 ng/mL, ΔQTcF remains low, with a mean (upper limit of the 90% confidence interval) of 9.1 (17.9) milliseconds. This analysis enabled the characterization of the C-QTc relationship and prediction of QTc prolongation at the expected clinical and possible higher psilocybin doses.

Norpsilocin: freebase and fumarate salt

The solid-state structures of the naturally occurring psychoactive tryptamine norpsilocin {4-hy-droxy-N-methyl-tryptamine (4-HO-NMT); systematic name: 3-[2-(methyl-amino)-eth-yl]-1H-indol-4-ol}, C11H14N2O, and its fumarate salt (4-hy-droxy-N-methyl-tryptammonium fumarate; systematic name: bis-{[2-(4-hy-droxy-1H-indol-3-yl)eth-yl]methyl-aza-nium} but-2-enedioate), C11H15N2O+·0.5C4H2O4 2-, are reported. The freebase of 4-HO-NMT has a single mol-ecule in the asymmetric unit joined together by N-H⋯O and O-H⋯O hydrogen bonds in a two-dimensional network parallel to the (100) plane. The ethyl-amine arm of the tryptamine is modeled as a two-component disorder with a 0.895 (3) to 0.105 (3) occupancy ratio. The fumarate salt of 4-HO-NMT crystallizes with a tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The ions are joined together by N-H⋯O and O-H⋯O hydrogen bonds to form a three-dimensional framework, as well as π-π stacking between the six-membered rings of inversion-related indoles (symmetry operation: 2 - x, 1 - y, 2 - z).

An exploratory study of experiences with conventional eating disorder treatment and ceremonial ayahuasca for the healing of eating disorders

PURPOSE

Ayahuasca is a traditional Amazonian medicine that is currently being researched for its potential in treating a variety of mental disorders. This article reports on exploratory qualitative research relating to participant experiences with ceremonial ayahuasca drinking and conventional treatment for eating disorders (EDs). It also explores the potential for ayahuasca as an adjunctive ED treatment.

METHODS

Thirteen individuals previously diagnosed with an ED participated in a semi-structured interview contrasting their experiences with conventional ED treatment with experiences from ceremonial ayahuasca. The interviews were analyzed using thematic analysis.

RESULTS

Participant reports were organized with key themes including that ayahuasca: led to rapid reductions in ED thoughts and symptoms; allowed for the healing of the perceived root of the ED; helped to process painful feelings and memories; supported the internalization of greater self-love and self-acceptance; and catalyzed spiritual elements of healing.

CONCLUSIONS

The results suggest that ayahuasca may have potential as a valuable therapeutic tool, and further research-including carefully controlled clinical trials-is warranted.

LEVEL OF EVIDENCE

Level V, qualitative descriptive study.

Bis(4-hy-droxy-N-isopropyl-N-methyl-trypt-ammo-nium) fumarate: a new crystalline form of miprocin

The title compound, bis-(4-hy-droxy-N-isopropyl-N-methyl-tryptammonium) (4-HO-MiPT) fumarate (systematic name: bis-{[2-(4-hy-droxy-1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium} but-2-enedioate), 2C14H21N2O+·C4H2O4 2-, has a singly protonated tryptammonium cation and one half of a fumarate dianion in the asymmetric unit. The tryptammonium and fumarate ions are held together in one-dimensional chains by N-H⋯O and O-H⋯O hydrogen bonds. These chains are a combination of R 4 2(20) rings, and C 2 2(15) and C 4 4(30) parallel chains along (110). They are further consolidated by N-H⋯π inter-actions. There are two two-component types of disorder impacting the tryptammonium fragment with a 0.753 (7):0.247 (7) occupancy ratio and one of the fumarate oxygen atoms with a 0.73 (8):0.27 (8) ratio.

Self-reported negative outcomes of psilocybin users: A quantitative textual analysis

Psilocybin, a substance mainly found in mushrooms of the genus psilocybe, has been historically used for ritualistic, recreational and, more recently, medicinal purposes. The scientific literature suggests low toxicity, low risk of addiction, overdose, or other causes of injury commonly caused by substances of abuse, with growing interest in the use of this substance for conditions such as treatment-resistant depression. However, the presence of negative outcomes linked to psilocybin use is not clear yet. The objective of this study is to investigate the negative effects of psilocybin consumption, according to the users' own perception through self-reports extracted from an online platform. 346 reports were analyzed with the assistance of the IRAMUTEQ textual analysis software, adopting the procedures of Descending Hierarchical Classification, Correspondence Factor Analysis and Specificities Analysis. The text segments were grouped in 4 main clusters, describing thinking distortions, emergencies, perceptual alterations and the administration of the substance. Bad trips were more frequent in female users, being associated with thinking distortions. The use of multiple doses of psilocybin in the same session or its combination with other substances was linked to the occurrence of long-term negative outcomes, while the use of mushrooms in single high doses was linked to medical emergencies. These results can be useful for a better understanding of the effects of psilocybin use, guiding harm-reduction initiatives.

Psychological flexibility mediates the relations between acute psychedelic effects and subjective decreases in depression and anxiety

Prior research has shown that acute subjective psychedelic effects are associated with both spontaneous and intended changes in depression and anxiety. Psychedelics are also theorized to produce increases in psychological flexibility, which could explain decreases in depression and anxiety following a psychedelic experience. Therefore, the present cross-sectional survey study sought to examine whether psychological flexibility mediated the relationship between acute psychedelic experiences and spontaneous or intended changes in depression and anxiety among a large international sample of people who reported having used a psychedelic (n=985; male=71.6%; Caucasian/white=84.1%; M age=32.2, SD=12.6). A regression analysis showed that acute effects (i.e., mystical and insightful effects) were significantly associated with decreases in depression/anxiety following a psychedelic experience. A path analysis revealed that, while controlling for age and sex, increases in psychological flexibility fully mediated the effect of mystical and insightful experiences on decreases in depression and anxiety following a psychedelic experience. This suggests that psychological flexibility may be an important mediator of the therapeutic effects of psychedelic drugs. Future prospective experimental studies should examine the effect of psychedelic drug administration on psychological flexibility in order to gain a better understanding of the psychological processes that predict therapeutic effects of psychedelics.

Adverse pharmacokinetic interactions between illicit substances and clinical drugs

Adverse pharmacokinetic interactions between illicit substances and clinical drugs are of a significant health concern. Illicit substances are taken by healthy individuals as well as by patients with medical conditions such as mental illnesses, acquired immunodeficiency syndrome, diabetes mellitus and cancer. Many individuals that use illicit substances simultaneously take clinical drugs meant for targeted treatment. This concomitant usage can lead to life-threatening pharmacokinetic interactions between illicit substances and clinical drugs. Optimal levels and activity of drug-metabolizing enzymes and drug-transporters are crucial for metabolism and disposition of illicit substances as well as clinical drugs. However, both illicit substances and clinical drugs can induce changes in the expression and/or activity of drug-metabolizing enzymes and drug-transporters. Consequently, with concomitant usage, illicit substances can adversely influence the therapeutic outcome of coadministered clinical drugs. Likewise, clinical drugs can adversely affect the response of coadministered illicit substances. While the interactions between illicit substances and clinical drugs pose a tremendous health and financial burden, they lack a similar level of attention as drug-drug, food-drug, supplement-drug, herb-drug, disease-drug, or other substance-drug interactions such as alcohol-drug and tobacco-drug interactions. This review highlights the clinical pharmacokinetic interactions between clinical drugs and commonly used illicit substances such as cannabis, cocaine and 3, 4-Methylenedioxymethamphetamine (MDMA). Rigorous efforts are warranted to further understand the underlying mechanisms responsible for these clinical pharmacokinetic interactions. It is also critical to extend the awareness of the life-threatening adverse interactions to both health care professionals and patients.

Twenty percent better with 20 micrograms? A qualitative study of psychedelic microdosing self-rapports and discussions on YouTube

BACKGROUND

Psychedelic microdosing is the trending practice of using tiny repeated doses of psychedelic substances to facilitate a range of supposed benefits. With only a few published studies to date, the subject is still under-researched, and more knowledge is warranted. Social media and internet discussion forums have played a vital role in the growing visibility of the microdosing phenomenon, and the present study utilized YouTube contents to improve comprehension of the microdosing practice as well as the social interactions and discussions around microdosing.

METHODS

Microdosing self-disclosure in YouTube videos and their following comments were qualitatively analyzed by inductive thematic analysis. Various software was utilized to enable gathering and sorting relevant data.

RESULTS

Microdosing of psychedelic substances, primarily LSD and psilocybin, was used for therapeutic and enhancement purposes, and predominantly beneficial effects were reported. Many different applications and outcomes were discussed, and therapeutic effects for depression appeared especially noteworthy. Intentions for use were recognized as an influencing factor for the progression and outcomes of microdosing. The function of social interactions was mainly to discuss views on the microdosing phenomenon, strategies for optimal results, minimize risks, and share emotional support.

CONCLUSIONS

Potentially, microdosing could provide some of the same benefits (for certain conditions) as full-dose interventions with less risk of adverse reactions related to the sometimes intense experiences of higher doses. Microdosing may well also mean additional benefits, as well as risks, through the repeated exposure over extended periods.

Microdosing psychedelics: Motivations, subjective effects and harm reduction

BACKGROUND

In recent years there has been growing media attention on microdosing psychedelics (e.g., LSD, psilocybin). This refers to people routinely taking small doses of psychedelic substances to improve mental health and wellbeing, or to enhance cognitive performance. Research evidence is currently limited. This paper examines microdosing motivations, dosing practices, perceived short-term benefits, unwanted effects, and harm reduction practices.

METHODS

An international online survey was conducted in 2018 examining people's experiences of using psychedelics. Eligible participants were aged 16 years or older, had used psychedelics and could comprehend written English. This paper focuses on 525 participants who were microdosing psychedelics at the time of the survey.

RESULTS

Participants were primarily motivated to microdose to improve mental health (40%), for personal development (31%) and cognitive enhancement (18%). Most were microdosing with psilocybin (55%) or LSD/1P-LSD (48%). Principal components analysis generated three factors examining perceived short-term benefits of microdosing: improved mood and anxiety, enhanced connection to others and environment, and cognitive enhancement; and three factors examining negative and potentially unwanted effects: stronger-than-expected psychedelic effects, anxiety-related effects, and physical adverse effects. Most participants (78%) reported at least one harm reduction practice they routinely performed while microdosing.

CONCLUSION

Our findings suggest that people microdosing are commonly doing so as a self-managed therapy for mental health, either as an alternative or adjunct to conventional treatments. This is despite psychedelics remaining prohibited substances in most jurisdictions. Recent findings from clinical trials with standard psychedelic doses for depression and anxiety suggest that a neurobiological effect beyond placebo is not unreasonable. Randomised controlled trials are needed, complemented by mixed methods social science research and the development of novel resources on microdosing harm reduction.

Psychedelic Microdosing: A Subreddit Analysis

Self-administration of very low doses of psychedelic drugs to improve mental health and wellbeing and enhance cognitive function, known as microdosing, has received recent media attention, but little research has been conducted. We conducted a content analysis of discussions about microdosing from the online forum Reddit. We examined motivations, dosing practices, and perceived benefits and limitations of microdosing. Motivations included self-management of mental health issues, improvement of psychosocial wellbeing, and cognitive enhancement. Self-reported benefits included cognitive and creative enhancement, reduced depression and anxiety, enhanced self-insight and mindfulness, improved mood and attitude toward life, improved habits and health behaviors, and improved social interactions and interpersonal connections. Perceived limitations included issues related to dosing, adverse physical effects, taking illegal substances, limited or no mental health or cognitive improvement, increased anxiety, unpleasant "off" days, only short-term benefits, and concerns about dependence and drug-related risks. Standard doses of psychedelic drugs provided in therapeutic settings have potential as novel treatments for some mental health conditions, but clinical research is needed to understand if this is also the case for microdosing. In the meantime, harm reduction resources should be developed and made available to provide the best available information on the safer use of self-administered psychedelics.

Fully automated head-twitch detection system for the study of 5-HT2A receptor pharmacology in vivo

Head-twitch behavior (HTR) is the behavioral signature of psychedelic drugs upon stimulation of the serotonin 5-HT_2A receptor (5-HT_2AR) in rodents. Following the previous report of a semi-automated detection of HTR based on the dynamics of mouse's head movement, here we present a system for the identification of individual HTR events in a fully automated fashion. The validity of this fully automated HTR detection system was tested with the psychedelic drug DOI in 5-HT_2AR-KO mice, and via evaluation of potential sources of false-positive and false-negative HTR events. The increased throughput in data processing achieved via automation afforded the possibility of conducting otherwise time consuming HTR time-course studies. To further assess the versatility of our system, we also explored the pharmacological interactions between 5-HT_2AR and the metabotropic glutamate receptor 2 (mGluR2). Our data demonstrate the potentiation effect of the mGluR2/3 antagonist LY341495 on DOI-induced HTR, as well as the HTR-blocking effect of the mGluR2/3 agonist and antipsychotic drug in development LY404039. This fully automated system can contribute to speed up our understanding of 5-HT_2AR's pharmacology and its characteristic behavioral outputs in rodents.

In vivo production of psilocybin in E. coli

Psilocybin, the prodrug of the psychoactive molecule psilocin, has demonstrated promising results in clinical trials for the treatment of addiction, depression, and post-traumatic stress disorder. The development of a psilocybin production platform in a highly engineerable microbe could lead to rapid advances towards the bioproduction of psilocybin for use in ongoing clinical trials. Here, we present the development of a modular biosynthetic production platform in the model microbe, Escherichia coli. Efforts to optimize and improve pathway performance using multiple genetic optimization techniques were evaluated, resulting in a 32-fold improvement in psilocybin titer. Further enhancements to this genetically superior strain were achieved through fermentation optimization, ultimately resulting in a fed-batch fermentation study, with a production titer of 1.16 g/L of psilocybin. This is the highest psilocybin titer achieved to date from a recombinant organism and a significant step towards demonstrating the feasibility of industrial production of biologically-derived psilocybin.

The fumarate salts of the N-isopropyl-N-methyl derivatives of DMT and psilocin

The solid-state structures of the salts of two substituted tryptamines, namely N-isopropyl-N-methyl-tryptaminium (MiPT) fumarate {systematic name: [2-(1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium 3-carb-oxy-prop-2-enoate}, C14H21N2 +·C4H3O4 -, and 4-hy-droxy-N-isopropyl-N-methyl-tryptaminium (4-HO-MiPT) fumarate monohydrate {systematic name: [2-(4-hy-droxy-1H-indol-3-yl)eth-yl](meth-yl)propan-2-yl-aza-nium 3-carb-oxy-prop-2-enoate monohydrate}, C14H21N2O+·C4H3O4 -·H2O, are reported. Both salts possess a proton-ated tryptammonium cation and a 3-carb-oxy-acrylate (hydrogen fumarate) anion in the asymmetric unit; the 4-HO-MiPT structure also contains a water mol-ecule of crystallization. Both cations feature disorder of the side chain over two orientations, in a 0.630 (3):0.370 (3) ratio for MiPT and a 0.775 (5):0.225 (5) ratio for 4-HO-MiPT. In both extended structures, N-H⋯O and O-H⋯O hydrogen bonds generate infinite two-dimensional networks.

Opportunities in Novel Psychotropic Drug Design from Natural Compounds

Multiple initiatives at the national and international level support natural drug discovery. Psychiatrists and patients are not well informed about natural psychotropics in general. Existing antidepressant and antipsychotic drugs were developed from atropine, a natural product. Subsequent drug developments were largely based on extension and modification of earlier molecular scaffolds. This limits their mechanisms of action to similar neuropathways. Natural psychotropic substances, particularly those with hallucinogenic and psychedelic properties and different chemical structures, may serve as new paths to novel psychotropic drug development.

N-Methyl-N-propyltryptamine (MPT)

The title compound {systematic name: [2-(1H-indol-3-yl)ethyl](methyl)propylamine}, C14H20N2, has a single molecule in the asymmetric unit. The molecules in the unit cell are held together in infinite one-dimensional chains along [010] through N—H...N hydrogen bonds between indole H atoms and trialkylamine N atoms.

Classic psychedelics: the special role of the visual system

Here, we briefly overview the various aspects of classic serotonergic hallucinogens reported by a number of studies. One of the key hypotheses of our paper is that the visual effects of psychedelics might play a key role in resetting fears. Namely, we especially focus on visual processes because they are among the most prominent features of hallucinogen-induced hallucinations. We hypothesize that our brain has an ancient visual-based (preverbal) intrinsic cognitive process that, during the transient inhibition of top-down convergent and abstract thinking (mediated by the prefrontal cortex) by psychedelics, can neutralize emotional fears of unconscious and conscious life experiences from the past. In these processes, the decreased functional integrity of the self-referencing processes of the default mode network, the modified multisensory integration (linked to bodily self-consciousness and self-awareness), and the modified amygdala activity may also play key roles. Moreover, the emotional reset (elimination of stress-related emotions) by psychedelics may induce psychological changes and overwrite the stress-related neuroepigenetic information of past unconscious and conscious emotional fears.

5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) used in a naturalistic group setting is associated with unintended improvements in depression and anxiety

BACKGROUND

A recent epidemiological study suggested that 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) used for spiritual and recreational reasons is associated with subjective improvement in depression and anxiety. Further exploration of the potential psychotherapeutic effects of 5-MeO-DMT could inform future clinical trials.

OBJECTIVES

We examined self-reported improvement in depression and anxiety among people who use 5-MeO-DMT in a group setting with structured procedures guiding dose and administration of 5-MeO-DMT. Such procedures also include activities for the preparation of, and support during/following sessions, which are similar to procedures used in clinical trials of hallucinogen administration. Next, we examined whether depression or anxiety were improved following use, and whether the acute subjective effects (mystical/challenging) or beliefs about the 5-MeO-DMT experience were associated with improvements in these conditions.

METHODS

Respondents (n = 362; M_age = 47.7; Male = 55%; White/Caucasian = 84%) completed an anonymous web-based survey.

RESULTS

Of those reporting having been diagnosed with depression (41%) or anxiety (48%), most reported these conditions were improved (depression = 80%; anxiety = 79%) following 5-MeO-DMT use, and fewer reported they were unchanged (depression = 17%; anxiety = 19%) or worsened (depression = 3%; anxiety = 2%). Improvement in depression/anxiety conditions were associated with greater intensity of mystical experiences and higher ratings of the spiritual significance and personal meaning of the 5-MeO-DMT experience. There were no associations between depression or anxiety improvement and the intensity of acute challenging physical/psychological effects during the 5-MeO-DMT experience.

CONCLUSIONS

Future prospective controlled clinical pharmacology studies should examine the safety and efficacy of 5-MeO-DMT administration for relieving depression and anxiety.

"Go Ask Alice": The Case for Researching Schedule I Drugs

The available treatments for disorders affecting large segments of the population are often costly, complex, and only marginally effective, and many have numerous side effects. These disorders include dementias, debilitating neurological disorders, the multiple types of drug addiction, and the spectrum of mental health disorders.Preliminary studies have shown that a variety of psychedelic and similar U.S. Drug Enforcement Administration Schedule I drugs may offer better treatment options than those that currently exist and pose potentially the same or even less risk than do legal psychoactive (alcohol, caffeine, nicotine) and nonpsychoactive (aspirin, acetaminophen, ibuprofen) substances. The pharmaceutical industry and academia, however, have largely avoided this avenue of research.Fairness to the affected populations demands that these drugs be adequately studied and, if they or their congeners are shown to be effective, made available with the proper caveats, instructions, and protections that other potentially abused medications (e.g., narcotics) receive. These substances may prove to relieve patients' struggles with less effective treatments and decrease mortality from nontreatment of some conditions.

Production Options for Psilocybin: Making of the Magic

The fungal genus Psilocybe and other genera comprise numerous mushroom species that biosynthesize psilocybin (4-phosphoryloxy-N,N-dimethyltryptamine). It represents the prodrug to its dephosphorylated psychotropic analogue, psilocin. The colloquial term "magic mushrooms" for these fungi alludes to their hallucinogenic effects and to their use as recreational drugs. However, clinical trials have recognized psilocybin as a valuable candidate to be developed into a medication against depression and anxiety. We here highlight its recently elucidated biosynthesis, the concurrently developed concept of enzymatic in vitro and heterologous in vivo production, along with previous synthetic routes. The prospect of psilocybin as a promising therapeutic may entail an increased demand, which can be met by biotechnological production. Therefore, we also briefly touch on psilocybin's therapeutic relevance and pharmacology.

Predicting Responses to Psychedelics: A Prospective Study

Responses to psychedelics are notoriously difficult to predict, yet significant work is currently underway to assess their therapeutic potential and the level of interest in psychedelics among the general public appears to be increasing. We aimed to collect prospective data in order to improve our ability to predict acute- and longer-term responses to psychedelics. Individuals who planned to take a psychedelic through their own initiative participated in an online survey (www.psychedelicsurvey.com). Traits and variables relating to set, setting and the acute psychedelic experience were measured at five different time points before and after the experience. Principle component and regression methods were used to analyse the data. Sample sizes for the five time points were N = 654, N = 535, N = 379, N = 315, and N = 212 respectively. Psychological well-being was increased 2 weeks after a psychedelic experience and remained at this level after 4 weeks. Higher ratings of a “mystical-type experience” had a positive effect on the change in well-being after a psychedelic experience, whereas the other acute psychedelic experience measures, i.e., “challenging experience” and “visual effects”, did not influence the change in well-being after the psychedelic experience. Having “clear intentions” for the experience was conducive to mystical-type experiences. Having a positive “set” as well as having the experience with intentions related to “recreation” were both found to decrease the likelihood of having a challenging experience. The baseline trait “absorption” and higher drug doses promoted all aspects of the acute experience, i.e., mystical-type and challenging experiences, as well as visual effects. When comparing the relative contribution of different types of variables in explaining the variance in the change in well-being, it seemed that baseline trait variables had the strongest effect on the change in well-being after a psychedelic experience. These results confirm the importance of extra-pharmacological factors in determining responses to a psychedelic. We view this study as an early step towards the development of empirical guidelines that can evolve and improve iteratively with the ultimate purpose of guiding crucial clinical decisions about whether, when, where and how to dose with a psychedelic, thus helping to mitigate risks while maximizing potential benefits in an evidence-based manner.

The abuse potential of medical psilocybin according to the 8 factors of the Controlled Substances Act

This review assesses the abuse potential of medically-administered psilocybin, following the structure of the 8 factors of the US Controlled Substances Act (CSA). Research suggests the potential safety and efficacy of psilocybin in treating cancer-related psychiatric distress and substance use disorders, setting the occasion for this review. A more extensive assessment of abuse potential according to an 8-factor analysis would eventually be required to guide appropriate schedule placement. Psilocybin, like other 5-HT2A agonist classic psychedelics, has limited reinforcing effects, supporting marginal, transient non-human self-administration. Nonetheless, mushrooms with variable psilocybin content are used illicitly, with a few lifetime use occasions being normative among users. Potential harms include dangerous behavior in unprepared, unsupervised users, and exacerbation of mental illness in those with or predisposed to psychotic disorders. However, scope of use and associated harms are low compared to prototypical abused drugs, and the medical model addresses these concerns with dose control, patient screening, preparation and follow-up, and session supervision in a medical facility. CONCLUSIONS: (1) psilocybin has an abuse potential appropriate for CSA scheduling if approved as medicine; (2) psilocybin can provide therapeutic benefits that may support the development of an approvable New Drug Application (NDA) but further studies are required which this review describes; (3) adverse effects of medical psilocybin are manageable when administered according to risk management approaches; and (4) although further study is required, this review suggests that placement in Schedule IV may be appropriate if a psilocybin-containing medicine is approved. This article is part of the Special Issue entitled 'Psychedelics: New Doors, Altered Perceptions'.

DARK Classics in Chemical Neuroscience: Psilocybin

Psilocybin is found in a family of mushrooms commonly known as "magic mushrooms" that have been used throughout history to induce hallucinations. In the late 1950s Albert Hofmann, of Sandoz Laboratories, identified and synthesized the psychoactive compounds psilocybin and psilocin which are found in psilocybe mushrooms. Psilocybin was marketed by Sandoz as Indocybin for basic psychopharmacological and therapeutic clinical research. Psilocybin saw a rapid rise in popularity during the 1960s and was classed as a Schedule I drug in 1970. This led to a significant decrease in psilocybin research. Recently, however, preliminary studies with psilocybin have shown promise as potential for the treatment of obsessive compulsive disorder, alcohol addiction, tobacco addiction, and major depressive disorder, and the treatment of depression in terminally ill cancer patients. This review describes in detail the synthesis, metabolism, pharmacology, adverse drug reactions, and importance of psilocybin to neuroscience in the past and present.

Double-blind comparison of the two hallucinogens psilocybin and dextromethorphan: effects on cognition

OBJECTIVES

Classic psychedelics (serotonin 2A receptor agonists) and dissociative hallucinogens (NMDA receptor antagonists), though differing in pharmacology, may share neuropsychological effects. These drugs, however, have undergone limited direct comparison. This report presents data from a double-blind, placebo-controlled within-subjects study comparing the neuropsychological effects of multiple doses of the classic psychedelic psilocybin with the effects of a single high dose of the dissociative hallucinogen dextromethorphan (DXM).

METHODS

Twenty hallucinogen users (11 females) completed neurocognitive assessments during five blinded drug administration sessions (10, 20, and 30 mg/70 kg psilocybin; 400 mg/70 kg DXM; and placebo) in which participants and study staff were informed that a large range of possible drug conditions may have been administered.

RESULTS

Global cognitive impairment, assessed using the Mini-Mental State Examination during peak drug effects, was not observed with psilocybin or DXM. Orderly and dose-dependent effects of psilocybin were observed on psychomotor performance, working memory, episodic memory, associative learning, and visual perception. Effects of DXM on psychomotor performance, visual perception, and associative learning were in the range of effects of a moderate to high dose (20 to 30 mg/70 kg) of psilocybin.

CONCLUSIONS

This was the first study of the dose effects of psilocybin on a large battery of neurocognitive assessments. Evidence of delirium or global cognitive impairment was not observed with either psilocybin or DXM. Psilocybin had greater effects than DXM on working memory. DXM had greater effects than all psilocybin doses on balance, episodic memory, response inhibition, and executive control.

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.

Psychedelics and music: neuroscience and therapeutic implications

From the beginning of therapeutic research with psychedelics, music listening has been consistently used as a method to guide or support therapeutic experiences during the acute effects of psychedelic drugs. Recent findings point to the potential of music to support meaning-making, emotionality, and mental imagery after the administration of psychedelics, and suggest that music plays an important role in facilitating positive clinical outcomes of psychedelic therapy. This review explores the history of, contemporary research on, and future directions regarding the use of music in psychedelic research and therapy, and argues for more detailed and rigorous investigation of the contribution of music to the treatment of psychiatric disorders within the novel framework of psychedelic therapy.

Psychedelic-Assisted Psychotherapy: A Paradigm Shift in Psychiatric Research and Development

Mental disorders are rising while development of novel psychiatric medications is declining. This stall in innovation has also been linked with intense debates on the current diagnostics and explanations for mental disorders, together constituting a paradigmatic crisis. A radical innovation is psychedelic-assisted psychotherapy (PAP): professionally supervised use of ketamine, MDMA, psilocybin, LSD and ibogaine as part of elaborated psychotherapy programs. Clinical results so far have shown safety and efficacy, even for “treatment resistant” conditions, and thus deserve increasing attention from medical, psychological and psychiatric professionals. But more than novel treatments, the PAP model also has important consequences for the diagnostics and explanation axis of the psychiatric crisis, challenging the discrete nosological entities and advancing novel explanations for mental disorders and their treatment, in a model considerate of social and cultural factors, including adversities, trauma, and the therapeutic potential of some non-ordinary states of consciousness.

The epidemiology of 5-methoxy- N, N-dimethyltryptamine (5-MeO-DMT) use: Benefits, consequences, patterns of use, subjective effects, and reasons for consumption

BACKGROUND/AIM

5-Methoxy- N,N-dimethyltryptamine (5-MeO-DMT) is a psychoactive compound found in several plants and in high concentrations in Bufo alvarius toad venom. Synthetic, toad, and plant-sourced 5-MeO-DMT are used for spiritual and recreational purposes and may have psychotherapeutic effects. However, the use of 5-MeO-DMT is not well understood. Therefore, we examined patterns of use, motivations for consumption, subjective effects, and potential benefits and consequences associated with 5-MeO-DMT use.

METHODS

Using internet-based advertisements, 515 respondents ( M_age=35.4. SD=11.7; male=79%; White/Caucasian=86%; United States resident=42%) completed a web-based survey.

RESULTS

Most respondents consumed 5-MeO-DMT infrequently (<once/year), for spiritual exploration, and had used less than four times in their lifetime. The majority (average of 90%) reported moderate-to-strong mystical-type experiences ( M_intensity=3.64, SD=1.11; range 0-5; e.g., ineffability, timelessness, awe/amazement, experience of pure being/awareness), and relatively fewer (average of 37%) experienced very slight challenging experiences ( M_intensity=0.95, SD=0.91; range 0-5; e.g., anxiousness, fear). Less than half (39%) reported repeated consumption during the same session, and very few reported drug craving/desire (8%), or legal (1%), medical (1%), or psychiatric (1%) problems related to use. Furthermore, of those who reported being diagnosed with psychiatric disorders, the majority reported improvements in symptoms following 5-MeO-DMT use, including improvements related to post-traumatic stress disorder (79%), depression (77%), anxiety (69%), and alcoholism (66%) or drug use disorder (60%).

CONCLUSION

Findings suggest that 5-MeO-DMT is used infrequently, predominantly for spiritual exploration, has low potential for addiction, and might have psychotherapeutic effects. Future research should examine the safety and pharmacokinetics of 5-MeO-DMT administration in humans using rigorous experimental designs.