Adverse consequences of lysergic acid diethylamide

Psychoactive substances for the treatment of neuropsychiatric disorders

In the contemporary landscape of psychiatric medicine, critical advancements have been noted in the utilization of psychoactive substances such as hallucinogens, 3,4-methylenedioxymethamphetamine (MDMA), and ketamine for the treatment of severe mental health disorders. This review provides a detailed evaluation of these substances, focusing on their mechanisms of action and the profound clinical outcomes observed in controlled environments. Hallucinogens like lysergic acid diethylamide and psilocybin primarily target the 5-HT2A receptor agonist-2 (5-HT2AR), inducing substantial perceptual and cognitive shifts that facilitate deep psychological introspection and significant therapeutic advances, particularly in patients suffering from depression and anxiety disorders. MDMA, influencing multiple neurotransmitter systems including 5-Hydroxytryptamine (5-HT), dopamine, and norepinephrine, has been demonstrated to effectively alleviate symptoms of post-traumatic stress disorder, enhancing patients' emotional engagement and resilience during psychotherapy. Meanwhile, ketamine, a glutamate receptor antagonist, rapidly alleviates depressive symptoms, offering a lifeline for individuals with treatment-resistant depression through its fast-acting antidepressant properties. The integration of these substances into psychiatric practice has shown promising results, fundamentally changing the therapeutic landscape for patients unresponsive to traditional treatment modalities. However, the potent effects of these agents also necessitate a cautious approach in clinical application, ensuring careful dosage control, monitoring, and risk management to prevent potential abuse and mitigate adverse effects.

The cyclical revival of psychedelics in psychiatric treatment

There is an increasing demand for effective treatments for depression, particularly for individuals grappling with treatment-resistant depression. Over recent years, a surge of interest has focused on exploring the safety and efficacy of psilocybin as a potential treatment for depression. However, preliminary findings from phase 2 studies have been inconclusive, prompting critical examination of issues such as maintaining blinding and the role of adjunctive psychotherapy. The maintenance of double-blinding and the role of adjunctive psychotherapy introduce biases that complicate the attainment of conclusive results in clinical research. Examining historical data reveals a recurrent pattern linked to the use of psychoactive substances, which starts with an excess of optimism and ends with general addictive behaviors and a heightened risk of serious public health problems. Considering these findings, a cautious and measured approach is imperative, given that the efficacy and safety of psilocybin treatment have yet to be unequivocally established. The potential for excessive optimism among researchers is a notable concern, as unwarranted enthusiasm may inadvertently facilitate the widespread adoption of this treatment without sufficient empirical support. In navigating the complexities of depression treatment, it is necessary to strike a balance between innovation and prudence to ensure evidence-based advancement of therapeutic approaches.

[Towards a Better understanding of Persisting Perceptual Disturbances following the use of Classic Psychedelics.]

Klassische Psychedelika wie Psilocybin, Lysergsäurediethylamid (LSD), Ayahuasca oder 5-Methoxy-Dimethyltryptamin (5-MeO-DMT) stehen wieder vermehrt im Fokus des psychiatrisch-psychotherapeutischen und neurowissenschaftlichen Interesses. Dies ist vor allem auf aktuelle klinische Studien zurückzuführen, die einen möglichen therapeutischen Nutzen von Psychedelika in der Behandlung verschiedener psychischer Störungen nahelegen, wie bei therapieresistenten Depressionen, Abhängigkeitserkrankungen, Angststörungen und existentiellen Ängsten bei lebensbedrohlichen körperlichen Erkrankungen 1 2 3 4. Trotz der beobachteten vielversprechenden Effekte ist es wichtig zu betonen, dass Psychedelika auch potenzielle Risiken bergen, die sie von vielen anderen psychoaktiven Substanzen unterscheiden. Diese liegen in der besonderen Phänomenologie der Wirkungen dieser Substanzen auf das zentrale Nervensystem und die menschliche Psyche begründet, in der zeitlichen Dynamik ihrer psychologischen Effekte, und in ihrem biologischen Wirkprofil.

Association of Hallucinogen Persisting Perception Disorder with Trait Neuroticism and Mental Health Symptoms

Hallucinogen Persisting Perception Disorder (HPPD) is considered rare in hallucinogen users although there are conflicting reports about its incidence and prevalence. HPPD may be more common in those with trait neuroticism. In this study, we invited hallucinogen and other drug users to complete an online questionnaire about their use of hallucinogens, their experience of HPPD symptoms, and their trait neuroticism and mental health symptoms. We received 802 responses with 415 of these containing adequate data for further analysis. 39.7% of responders reported symptoms corresponding to Type I HPPD, and 4.3% reported symptoms corresponding to Type II HPPD. We found no significant difference between neuroticism scores for participants with or without HPPD. Individuals with Type II HPPD were more likely to report mental health symptoms including anxiety, obsessional thoughts, paranoia, hypochondria and panic attacks (p < .05). We also found that individuals with Type II HPPD were more likely to report the use of 25I-NBOMe, dextromethorphan, nitrous oxide and benzodiazepines (p < .05). 47.3% of participants had never tested their drugs, making the attribution of HPPD severity to specific drugs difficult. Further work into the development of HPPD is required, particularly with the rise of hallucinogens as potential treatments for depression and other mental illnesses.

Abnormal Glutamatergic and Serotonergic Connectivity in Visual Snow Syndrome and Migraine with Aura

OBJECTIVE

Neuropharmacological changes in visual snow syndrome (VSS) are poorly understood. We aimed to use receptor target maps combined with resting functional magnetic resonance imaging (fMRI) data to identify which neurotransmitters might modulate brain circuits involved in VSS.

METHODS

We used Receptor-Enriched Analysis of Functional Connectivity by Targets (REACT) to estimate and compare the molecular-enriched functional networks related to 5 neurotransmitter systems of patients with VSS (n = 24), healthy controls (HCs; n = 24), and migraine patients ([MIG], n = 25, 15 of whom had migraine with aura [MwA]). For REACT we used receptor density templates for the transporters of noradrenaline, dopamine, and serotonin, GABA-A and NMDA receptors, as well as 5HT1B and 5HT2A receptors, and estimated the subject-specific voxel-wise maps of functional connectivity (FC). We then performed voxel-wise comparisons of these maps among HCs, MIG, and VSS.

RESULTS

Patients with VSS had reduced FC in glutamatergic networks localized in the anterior cingulate cortex (ACC) compared to HCs and patients with migraine, and reduced FC in serotoninergic networks localized in the insula, temporal pole, and orbitofrontal cortex compared to controls, similar to patients with migraine with aura. Patients with VSS also showed reduced FC in 5HT2A -enriched networks, largely localized in occipito-temporo-parietal association cortices. As revealed by subgroup analyses, these changes were independent of, and analogous to, those found in patients with migraine with aura.

INTERPRETATION

Our results show that glutamate and serotonin are involved in brain connectivity alterations in areas of the visual, salience, and limbic systems in VSS. Importantly, altered serotonergic connectivity is independent of migraine in VSS, and simultaneously comparable to that of migraine with aura, highlighting a shared biology between the disorders. ANN NEUROL 2023;94:873-884.

Case analysis of long-term negative psychological responses to psychedelics

Recent controversies have arisen regarding claims of uncritical positive regard and hype surrounding psychedelic drugs and their therapeutic potential. Criticisms have included that study designs and reporting styles bias positive over negative outcomes. The present study was motivated by a desire to address this alleged bias by intentionally focusing exclusively on negative outcomes, defined as self-perceived 'negative' psychological responses lasting for at least 72 h after psychedelic use. A strong justification for this selective focus was that it might improve our ability to capture otherwise missed cases of negative response, enabling us to validate their existence and better examine their nature, as well as possible causes, which could inspire risk-mitigation strategies. Via advertisements posted on social media, individuals were recruited who reported experiencing negative psychological responses to psychedelics (defined as classic psychedelics plus MDMA) lasting for greater than 72 h since using. Volunteers were directed to an online questionnaire requiring quantitative and qualitative input. A key second phase of this study involved reviewing all of the submitted cases, identifying the most severe-e.g., where new psychiatric diagnoses were made or pre-existing symptoms made worse post psychedelic-use-and inviting these individuals to participate in a semi-structured interview with two members of our research team, during which participant experiences and backgrounds were examined in greater depth. Based on the content of these interviews, a brief summary of each case was compiled, and an explorative thematic analysis was used to identify salient and consistent themes and infer common causes. 32 individuals fully completed an onboarding questionnaire (56% male, 53% < age 25); 37.5% of completers had a psychiatric diagnosis that emerged after their psychedelic experience, and anxiety symptoms arose or worsened in 87%. Twenty of the seemingly severer cases were invited to be interviewed; of these, 15 accepted an in-depth interview that lasted on average 60 min. This sample was 40% male, mean age = 31 ± 7. Five of the 15 (i.e., 33%) reported receiving new psychiatric diagnoses after psychedelic-use and all fifteen reported the occurrence or worsening of psychiatric symptoms post use, with a predominance of anxiety symptoms (93%). Distilling the content of the interviews suggested the following potential causal factors: unsafe or complex environments during or surrounding the experience, unpleasant acute experiences (classic psychedelics), prior psychological vulnerabilities, high- or unknown drug quantities and young age. The current exploratory findings corroborate the reality of mental health iatrogenesis via psychedelic-use but due to design limitations and sample size, cannot be used to infer on its prevalence. Based on interview reports, we can infer a common, albeit multifaceted, causal mechanism, namely the combining of a pro-plasticity drug-that was often 'over-dosed'-with adverse contextual conditions and/or special psychological vulnerability-either by young age or significant psychiatric history. Results should be interpreted with caution due to the small sample size and selective sample and study focus.

Systematic review and rationale of using psychedelics in the treatment of cannabis use disorder

Introduction

Cannabis use disorder (CUD) is prevalent in ~2-5% of adults in the United States and is anticipated to increase as restrictions to cannabis decrease and tetrahydrocannabinol (THC) content in cannabis products increase. No FDA-approved medications for CUD are currently available, despite trials of dozens of re-purposed and novel drugs. Psychedelics have garnered interest as a therapeutic class in other substance use disorders, and self-report surveys suggest they may result in positive outcomes for CUD. Herein, we review the existing literature pertaining to psychedelic use in persons with or at risk for CUD and consider the potential rationale underpinning psychedelics as a treatment for CUD.

Methods

A systematic search was performed in several databases. Inclusion criteria were primary research reporting use of psychedelics or related substances and CUD for treatment in human subjects. Exclusion criteria were results including psychedelics or related substances without changes in cannabis use or risks associated with CUD.

Results

Three hundred and five unique results were returned. One article was identified using the non-classical psychedelic ketamine in CUD; three articles were identified as topically relevant based on their secondary data or consideration of mechanism. Additional articles were reviewed for purposes of background, review of safety considerations, and formulating rationale.

Conclusion

Limited data and reporting are available on the use of psychedelics in persons with CUD, and more research is needed given the anticipated increase in CUD incidence and increasing interest in psychedelic use. While psychedelics, broadly, have a high therapeutic index with infrequent serious adverse effects, particular adverse effects at risk in the CUD population, such as psychosis and cardiovascular events, should be considered. Possible mechanisms by which psychedelics have therapeutic potential in CUD are explored.

Could psychedelic drugs have a role in the treatment of schizophrenia? Rationale and strategy for safe implementation

Schizophrenia is a widespread psychiatric disorder that affects 0.5-1.0% of the world's population and induces significant, long-term disability that exacts high personal and societal cost. Negative symptoms, which respond poorly to available antipsychotic drugs, are the primary cause of this disability. Association of negative symptoms with cortical atrophy and cell loss is widely reported. Psychedelic drugs are undergoing a significant renaissance in psychiatric disorders with efficacy reported in several conditions including depression, in individuals facing terminal cancer, posttraumatic stress disorder, and addiction. There is considerable evidence from preclinical studies and some support from human studies that psychedelics enhance neuroplasticity. In this Perspective, we consider the possibility that psychedelic drugs could have a role in treating cortical atrophy and cell loss in schizophrenia, and ameliorating the negative symptoms associated with these pathological manifestations. The foremost concern in treating schizophrenia patients with psychedelic drugs is induction or exacerbation of psychosis. We consider several strategies that could be implemented to mitigate the danger of psychotogenic effects and allow treatment of schizophrenia patients with psychedelics to be implemented. These include use of non-hallucinogenic derivatives, which are currently the focus of intense study, implementation of sub-psychedelic or microdosing, harnessing of entourage effects in extracts of psychedelic mushrooms, and blocking 5-HT2A receptor-mediated hallucinogenic effects. Preclinical studies that employ appropriate animal models are a prerequisite and clinical studies will need to be carefully designed on the basis of preclinical and translational data. Careful research in this area could significantly impact the treatment of one of the most severe and socially debilitating psychiatric disorders and open an exciting new frontier in psychopharmacology.

Apophenia, absorption and anxiety: Evidence for individual differences in positive and negative experiences of Hallucinogen Persisting Perceptual Disorder

Background and Aims

Little is known about individual differences in Hallucinogen Persisting Perceptual Disorder (HPPD). This study investigated visual processing style and personality across two HPPD types (HPPD I and HPPD II) and a Non-HPPD group.

Methods

An online survey was delivered to participants sourced from online HPPD and psychedelic user groups and forums (N = 117). Using one-way ANOVA, respondents were compared across four measures of individual difference. Using logistic regression, a range of visual symptoms and experiences were investigated as potential predictors of group categorisation.

Results

The HPPD I group had higher absorption and visual apophenia scores than the other groups and was predicted by higher drug use. The HPPD II group showed significantly higher trait anxiety than both other groups. Across the HPPD groups, HPPD II categorisation was also predicted by increased negative precipitating experiences, lack of prior knowledge and pre-existing anxiety diagnoses.

Conclusions

Anxiety, negative precipitating experiences and lack of prior knowledge are associated with negative experiences of persistent visual symptoms following hallucinogen use, whilst higher absorption and visual apophenia are associated with positive or neutral experiences. Together these findings indicate that differences in personality may play a role in determining an individual's experience of HPPD, highlighting the role of individual difference research in expanding knowledge around HPPD.

Hallucinogenic Persisting Perception Disorder: A Case Series and Review of the Literature

Background

Hallucinogen persisting perception disorder (HPPD) is characterized by the re-emergence of perceptual symptoms experienced during acute hallucinogen intoxication following drug cessation. The underlying pathophysiology is poorly understood. We report the clinical characteristics and investigation findings of a series of HPPD cases with a literature review of previous case reports. We draw parallels between the features of HPPD and Visual Snow Syndrome (VSS).

Methods

Retrospective case series of 13 patients referred from neuro-ophthalmologists. Literature review with 24 HPPD case reports were identified through database search using the terms “hallucinogenic persisting perception disorder” OR “hallucinogen persisting perception disorder.”

Results

Lysergic acid diethylamide (LSD), 3,4-Methyl enedioxy methamphetamine (MDMA) and cannabinoid use was common. Cannabinoids and MDMA were mostly used in association with classical hallucinogens. The most frequent symptoms in our patients were visual snow, floaters, palinopsia, photophobia and nyctalopia. In the literature other symptoms included visual hallucinations altered motion perception, palinopsia, tracers and color enhancement. Ophthalmic and neurologic investigations were mostly normal. The majority of patients had ongoing symptoms. Two of our patients fully recovered—one after treatment with benzodiazepine and one without treatment. Twenty-five percent of cases from the literature fully recovered.

Conclusions

HPPD presents with heterogeneous visual phenomena on a background of previous classic and non-classic hallucinogen use. Ophthalmic investigations are typically normal. The symptoms of HPPD in our case series overlap with the typical features of Visual Snow Syndrome (VSS). Patients presenting with VSS should be screened for past recreational drug use. The DSM-5 description of HPPD does not include visual snow, nyctalopia, photophobia or floaters. A revision of the diagnostic criteria to include these symptoms may better reflect the typical clinical phenotype. Increased awareness of HPPD as a secondary cause of VSS can avoid extensive investigations. Controlled trials comparing primary and secondary VSS patients are needed to understand the pathophysiology better and optimize treatment for HPPD.

Pathological Delta Oscillations in Hallucinogen Persisting Perception Disorder: A Case Report

BACKGROUND

Hallucinogen persisting perception disorder (HPPD) is characterized by spontaneous recurrence of visual hallucinations or disturbances after previous consumption of hallucinogens, such as lysergic acid diethylamide (LSD). The underlying physiological mechanisms are unknown and there is no standardized treatment strategy available.

CASE PRESENTATION

A 33-year-old male patient presented with persistent visual distortions (halos around objects, intensified colors, positive after images, and trails following moving objects) that developed after repeated use of hallucinogenic drugs at the age of 18. Symptoms developed gradually and worsened several months later, resulting in various pharmacological and psychosocial treatment attempts that remained unsuccessful, however. At presentation, 32-channel electroencephalography (EEG) showed increased delta activity over the occipital brain regions, reminiscent of occipital intermittent rhythmic delta activity (OIRDA) usually seen in children. Two sessions of cathodal (inhibitory) transcranial direct current stimulation (tDCS) over 30 min attenuated visual hallucinations and occipital delta activity by approximately 60%. The response persisted for over four weeks.

CONCLUSION

Pathological delta activity over occipital brain regions may play an important role in the development and perpetuation of HPPD and can be attenuated by non-invasive brain stimulation.

Hallucinogen Use and Misuse in Older Adults

Hallucinogens, or psychedelics, are substances/drugs that have been used for over a millennium. The most well known are LSD, psilocybin, mescaline, and PCP. These substances may induce hallucinations as well as cause somatic and psychological symptoms. Because of the Controlled Substances Act of 1970, there has been very little research done to determine the long-term consequences or perhaps potential benefit of misuse and abuse of hallucinogens. Typically, these drugs are not abused but more often misused. Recently, there has been a renewed interest in these compounds, which may lead to possible therapeutic options.

On Perception and Consciousness in HPPD: A Systematic Review

Hallucinogen-persisting perception disorder (HPPD) features as a diagnostic category in the DSM-5, ICD-11, and other major classifications, but our knowledge of the phenomenology of the perceptual symptoms involved and the changes in consciousness during the characteristic “flashbacks” is limited. We systematically evaluated original case reports and case series on HPPD to define its phenomenology, associated (psycho)pathology, and course. Our search of PubMed and Embase yielded 66 relevant publications that described 97 people who, together, experienced 64 unique symptoms of HPPD. Of these, 76% concerned symptoms characteristic of Alice in Wonderland syndrome, over 50% non-visual symptoms, and 38% perceptual symptoms not clearly linked to prior intoxication states. This is in contrast with the DSM-5 diagnostic criteria for HPPD. Even though less than half of the patients showed a protracted disease course of over a year, a third achieved remission. However, in patients with co-occurring depression (with or without anxiety) HPPD symptoms persisted longer and treatment outcomes were more often negative. Thus, unlike the acute stages of psychedelic drug intoxication, which may be accompanied by altered states of consciousness, HPPD is rather characterized by changes in the content of consciousness and an attentional shift from exogenous to endogenous phenomena. Since HPPD is a more encompassing nosological entity than suggested in the DSM-5, we recommend expanding its diagnostic criteria. In addition, we make recommendations for clinical practice and future research.

Early LSD treatment in Denmark from 1960 to 1974: An analysis of possible and long-lasting changes in the adult personality following psychedelic treatment. A historical retrospective cohort study

ABSTRACT

In view of the renewed interest in psychedelics in psychiatry it is timely to analyze psychedelic treatment in historical cohorts. Recently the therapeutic efficacy of psychedelics has been linked to the so-called phenomenon of "connectedness." The aim of the present study was to explore whether long-lasting personality changes were observed in any of the 151 Danish psychiatric patients who were treated with Lysergic acid diethylamide (LSD) from 1960 to 1974.The exploration included a reanalysis of a subgroup as well from a 1964 Danish historical cohort. Medical records and other case materials of the above mentioned 151 patients are kept in the Danish State Archives. The present author was granted access to the LSD case materials in the Danish State Archives, and respected confidentiality per the Archives Law. According to the LSD Damages Law from 1986, they all received financial compensation for LSD-inflicted harm.Analysis did not reveal any personality changes such as "connectedness;" however, other lasting personality changes were observed in 2 to 4 patients and in quite a few patients unwanted effects persisted for weeks or months following acute treatment. In the present analysis of the 1964 cohort, the same percentage of patients improved with LSD treatment as in the historical analysis. In the latter, however, little attention was given to side effects, such as suicide attempts, suicides, and one homicide.Future psychedelic research with psychiatric patients should respect the potential toxicity of LSD and other psychedelics and meticulously monitor possible side effects.

Use and abuse of dissociative and psychedelic drugs in adolescence

Adolescence is a period of profound developmental changes, which run the gamut from behavioral and neural to physiological and hormonal. It is also a time at which there is an increased propensity to engage in risk-taking and impulsive behaviors like drug use. This review examines the human and preclinical literature on adolescent drug use and its consequences, with a focus on dissociatives (PCP, ketamine, DXM), classic psychedelics (LSD, psilocybin), and MDMA. It is the case for all the substances reviewed here that very little is known about their effects in adolescent populations. An emerging aspect of the literature is that dissociatives and MDMA produce mixed reinforcing and aversive effects and that the balance between reinforcement and aversion may differ between adolescents and adults, with consequences for drug use and addiction. However, many studies have failed to directly compare adults and adolescents, which precludes definitive conclusions about these consequences. Other important areas that are largely unexplored are sex differences during adolescence and the long-term consequences of adolescent use of these substances. We provide suggestions for future work to address the gaps we identified in the literature. Given the widespread use of these drugs among adolescent users, and the potential for therapeutic use, this work will be crucial to understanding abuse potential and consequences of use in this developmental stage.

Regioselective Formation of Substituted Indoles: Formal Synthesis of Lysergic Acid

A Diels-Alder reaction-based strategy for the synthesis of indoles and related heterocycles is reported. An intramolecular cycloaddition of alkyne-tethered 3-aminopyrones gives 4-substituted indolines in good yield and with complete regioselectivity. Additional substitution is readily tolerated in the transformation, allowing synthesis of complex and non-canonical substitution patterns. Oxidative conditions give the corresponding indoles. The strategy also allows the synthesis of carbazoles. The method was showcased in a formal synthesis of lysergic acid.

[Visual snow in hallucinogen-persisting perception disorder]

This article presents the case of a 24-year-old female patient who was referred to this department due to permanent flickering in front of both eyes. This flickering, described as being like visual snow in television, had started 1.5 years ago and was perceived to be very disturbing. Visual acuity, visual field and morphology of the anterior and posterior segment were bilaterally inconspicuous. A neurological examination including a magnetic resonance imaging of the cranium (cMRI) and visual evoked potentials (pattern-VEP) also showed no abnormalities. Furthermore, the patient suffered from schizophrenia. This also first occurred 1.5 years ago directly after consumption of a "narcotic cocktail" consisting of amphetamines, hallucinogens and alcohol. In a synopsis of the findings the patient was diagnosed with type II hallucinogen-persisting perception disorder. Treatment options for this disease are limited and the symptoms often remain permanently.

“Go ask Alice, when she’s 10-feet tall”: Psychosocial correlates to lifetime LSD use among a national sample of US adults

Introduction

Once thought a rarely used drug, LSD use is steadily increasing among US adults. A greater understanding of social factors and psychological determinants leading to lifetime LSD use can assist health educators and professionals in treating this growing problem. This study analyzed psychosocial factors related to LSD use among a national sample of adults.

Methods

A secondary data analysis of the 2017 National Survey on Drug Use and Health was performed.

Results

Results from the final multivariate logistic regression revealed that those who were male, African American or Hispanic, used alcohol, ecstasy, marijuana, inhalants, cocaine, and cigarettes before the age of 21 years, thought about suicide, got a kick out of doing things risky, and tested oneself to do risky things were more likely to use LSD.

Conclusions

This suggests that psychodynamic processes, for example, possible activation of emotional conflicts – can take place spontaneously – during ayahuasca intake in this particular setting. Some participants attributed symbolic meaning to the visionary content, which was more likely to take place in psychotherapeutically motivated clients. The specific setting influence as well as corresponding expectations of the participants in native wisdom could have considerable influence on experiences and interpretations, such as communication with entities as well as receiving personal teachings.

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.

Hallucinogen Persisting Perception Disorder: Etiology, Clinical Features, and Therapeutic Perspectives

Hallucinogen Persisting Perception Disorder (HPPD) is a rare, and therefore, poorly understood condition linked to hallucinogenic drugs consumption. The prevalence of this disorder is low; the condition is more often diagnosed in individuals with a history of previous psychological issues or substance misuse, but it can arise in anyone, even after a single exposure to triggering drugs. The aims of the present study are to review all the original studies about HPPD in order to evaluate the following: (1) the possible suggested etiologies; (2) the possible hallucinogens involved in HPPD induction; (3) the clinical features of both HPPD I and II; (4) the possible psychiatric comorbidities; and (5) the available and potential therapeutic strategies. We searched PubMed to identify original studies about psychedelics and Hallucinogen Persisting Perception Disorder (HPPD). Our research yielded a total of 45 papers, which have been analyzed and tabled to provide readers with the most updated and comprehensive literature review about the clinical features and treatment options for HPPD.

Alice in Wonderland Syndrome: A Historical and Medical Review

Alice in Wonderland syndrome is a disorienting neurological condition that affects human perception to the senses of vision, hearing, touch, sensation, and the phenomenon of time. Individuals affected with Alice in Wonderland syndrome can experience alterations in their perception of the size of objects or their own body parts, known as metamorphopsias. It is known to occur in conditions including migraine, epilepsy, and certain intoxicants and infectious diseases. The name refers to Lewis Carrol's well-known children's book Alice's Adventures in Wonderland, in which the title character experiences alterations of sensation in which she felt that her body had grown too tall or too small, or parts of her body were changing shape, size, or relationship to the rest of her body. The syndrome was described in 1952 by Caro Lippman, and given its name in 1955 by John Todd. The metamorphopsias characteristic of this condition are also sometimes referred to as Lilliputian hallucinations, a reference to the fictional island of Lilliput in the novel Gulliver's Travels, written by Jonathan Swift in 1726. As such, many literary and medical publications have roots in the description of this syndrome. The purpose of this review is to summarize the literary and historical significance of Alice in Wonderland syndrome, as well as to provide the reader with a medical overview of the condition.

LSD treatment in Scandinavia: emphasizing indications and short-term treatment outcomes of 151 patients in Denmark

BACKGROUND

New research has suggested the clinical use of lysergic acid diethylamide (LSD) and psilocybin in selected patient populations. However, concerns about the clinical use of LSD were advanced in a large Danish follow-up study that assessed 151 LSD-treated psychiatric patients approximately 25 years after their treatment in the 1960s.

AIMS

The purpose of the present study was to give a retrospective account of the short-term outcome of LSD treatment in these 151 Danish psychiatric patients.

METHODS

The LSD case material in the Danish State Archives consists of medical case records of 151 LSD-treated patients, who complained and received economic compensation with the LSD Damages Law. The author carefully read and reviewed the LSD case material.

RESULTS

LSD was used to treat a wide spectrum of mental disorders. Independent of diagnoses, 52 patients improved, and 48 patients worsened acutely with the LSD treatment. In a subgroup of 82 neurotic patients, the LSD dose-index (number of treatments multiplied by the maximal LSD dose) indicated the risk of acute worsening. In another subgroup of 19 patients with obsessive-compulsive neurosis, five patients later underwent psychosurgery. A small subgroup of 12 patients was treated with psilocybin. The long-term outcome was poor in most of the patients.

CONCLUSIONS

Despite the significant limitations to a retrospective design, this database warrants caution in mental health patients. The use of LSD and psilocybin in mental health patients may be associated with serious short- and long-term side effects. Until further trials with rigorous designs have cleared these drugs of their potential harms, their clinical utility in these groups of patients has not been fully clarified.

Socio-Cultural and Psychological Aspects of Contemporary LSD use in Germany

The current study uses a qualitative methodology to investigate socio-cultural and psychological aspects involved in the use of LSD and comparable psychedelic substances. To date, 26 narrative interviews have been conducted with 12 female and 14 male users aged 19 to 53 years. The resulting data were subjected to content analysis in several thematic areas. Subjective reports of LSD use and experiences are considered among the complex interrelationship of drug effects, individual and environmental factors, as well as in comparison to the results reported in earlier research. Preliminary results suggest the use of LSD is largely independent of the “party drugs” scene, although its users do embrace elements of alternative lifestyles and subcultures. The majority of participants report their LSD experiences to be of great importance and to have intellectual relevance for their individuation process and personality development. Exploration of the self and the desire to experience profound changes in their perception of the world are reported as primary motives for LSD use, in addition to its hedonistic value. Individual backgrounds, knowledge and patterns of reaction are found to strongly influence the character of the drug effects that are experienced. Next to a wide range of extra-pharmacological factors, various methods for actively modifying LSD induced states were discovered to determine the general character of LSD experiences. These are discussed with regard to their implications for the development of suitable harm reduction concepts.

REVIEW ■ : Long-lasting Effects of Recreational Drugs of Abuse on the Central Nervous System

Although a wealth of knowledge exists regarding the acute pharmacological effects of recreational drugs on the CNS, much less is known about the long-term toxic effects of recreational drugs on the CNS. Recent findings in nonhuman primates treated with amphetamine analogs, such as ±3,4-methylenedioxymetham phetamine (MDMA), indicate that these drugs can produce long-lasting, probably permanent, changes in brain serotonin innervation. Similarly, animals treated with phencyclidine (PCP) and related drugs develop neurodegenerative changes in selected brain regions. It seems clear, then, that some psychoactive drugs have the potential to produce persistent changes in CNS structure and, possibly, function. The goal of this article is to summarize current knowledge regarding the long-term effects of several popular recreational drugs, including MDMA and related amphetamine analogs, cocaine, marijuana, alcohol, PCP, lysergic acid (LSD), and opiates. Gaps in the current knowledge base are identified, and areas ripe for future research efforts are suggested. NEUROSCIENTIST 3:399-411, 1997

The Association of Salvia divinorum and Psychotic Disorders: A Review of the Literature and Case Series

The association of substance abuse and psychotic disorders is of interest to clinicians, academics, and lawmakers. Commonly abused substances, such as cannabis, cocaine, amphetamines, and alcohol, have all been associated with substance-induced psychosis. Hallucinogens can induce desired psychedelic effects and undesirable psychomimetic reactions. These are usually transient and resolve once the duration of action is over. Sometimes, these effects persist, causing distress and requiring intervention. This article focuses on the hallucinogenic substance Salvia divinorum, the use of which has been observed, particularly among youth worldwide. We present background information based on a review of the literature and on our own clinical encounters, as highlighted by two original case reports. We hypothesize that consumption of Salvia divinorum could be associated with the development of psychotic disorders. We propose that clinicians routinely inquire about the use of Salvia in patients with substance use disorders or psychotic illnesses. More research is required to assess any relationship between Salvia divinorum and psychosis. Additionally, we advocate increased public and medical awareness of this substance and other emerging drugs of abuse.

Forbidden therapies: Santo Daime, ayahuasca, and the prohibition of entheogens in Western society

Santo Daime, a Brazilian religion organized around a potent psychoactive beverage called ayahuasca, is now being practiced across Europe and North America. Deeming ayahuasca a dangerous "hallucinogen," most Western governments prosecute people who participate in Santo Daime. On the contrary, members of Santo Daime (called "daimistas") consider ayahuasca a medicinal sacrament (or "entheogen"). Empirical studies corroborate daimistas' claim that entheogens are benign and can be beneficial when employed in controlled contexts. Following from anthropology's goal of rendering different cultural logics as mutually explicable, this article intercedes in a misunderstanding between policies of prohibition and an emergent subculture of entheogenic therapy.

Toxicities associated with NBOMe ingestion-a novel class of potent hallucinogens: a review of the literature

BACKGROUND

A new class of synthetic hallucinogens called NBOMe has emerged as drugs of abuse.

OBJECTIVE

Our aim was to conduct a systematic review of published reports of toxicities associated with NBOMe ingestion.

METHODS

We searched PubMed for relevant English-language citations that described adverse effects from analytically confirmed human NBOMe ingestion. Demographic and clinical data were extracted.

RESULTS

A total of 10 citations met the criteria for inclusion, representing 20 individual patients. 25I-NBOMe was the most common analogue identified, followed by 25B-NBOMe and 25C-NBOMe. Fatalities were reported in 3 (15%) cases. Of all the patients, 7 (35%) were discharged after a period of observation, whereas 8 (40.0%) required admission to an intensive care unit. The most common adverse effects were agitation (85.0%), tachycardia (85.0%), and hypertension (65.0%). Seizures were reported in 8 (40.0%) patients. The most common abnormalities reported on laboratory tests were elevated level of creatinine kinase (45.0%), leukocytosis (25.0%), and hyperglycemia (20.0%).

CONCLUSION

NBOMe ingestion is associated with severe adverse effects. Clinicians need to have a high index of suspicion for NBOMe ingestion in patients reporting the recent use of hallucinogens.

Hallucinogen persisting perception disorder and the serotonergic system: a comprehensive review including new MDMA-related clinical cases

Hallucinogen persisting perception disorder (HPPD) is a drug-induced condition associated with inaccurate visual representations. Since the underlying mechanism(s) are largely unknown, this review aims to uncover aspects underlying its etiology. Available evidence on HPPD and drug-related altered visual processing was reviewed and the majority of HPPD cases were attributed to drugs with agonistic effects on serotonergic 5-HT₂A receptors. Moreover, we present 31 new HPPD cases that link HPPD to the use of ecstasy (MDMA), which is known to reverse serotonin reuptake and acts as agonist on 5-HT₂A receptors. The available evidence suggests that HPPD symptoms may be a result from a misbalance of inhibitory-excitatory activity in low-level visual processing and GABA-releasing inhibitory interneurons may be involved. However, high co-morbidities with anxiety, attention problems and derealization symptoms add complexity to the etiology of HPPD. Also, other perceptual disorders that show similarity to HPPD cannot be ruled out in presentations to clinical treatment. Taken together, evidence is still sparse, though low-level visual processing may play an important role. A novel finding of this review study, evidenced by our new cases, is that ecstasy (MDMA) use may also induce symptoms of HPPD.

Clinical characteristics of individuals with schizophrenia and hallucinogen persisting perception disorder: a preliminary investigation

OBJECTIVE

An unusual side effect of hallucinogen use is the appearance of hallucinogen persisting perception disorder (HPPD). Despite high rates of prior hallucinogen use among individuals with schizophrenia, there are insufficient data on the clinical characteristics of individuals with co-occurring schizophrenia and HPPD.

METHODS

Twenty-six hospitalized patients with schizophrenia and prior LSD use (12 with HPPD and 14 without HPPD) were recruited. Participants were clinically assessed using validated tools, and details regarding hospitalizations were retrieved from their medical records. Those patients who also had HPPD completed a questionnaire addressing HPPD-associated perceptual disturbances.

RESULTS

Participants were mostly male (n = 22, 84.6%) and had an average age of 32.3 (SD = 7.67). Nearly half (n = 12, 46.2%) met criteria for HPPD. No significant differences were found in sociodemographic and clinical characteristics (including response to antipsychotic medications and adverse effects) between the groups. Nine individuals (75%) in the schizophrenia and HPPD group reported the ability to identify specific precursory cues for the appearance of the HPPD-associated perceptual distortions, and 8 (67%) reported the ability to distinguish HPPD perceptual disturbances from those associated with their psychotic disorder.

CONCLUSIONS

Very little is known about the co-occurrence of schizophrenia and HPPD or the associated clinical implications. Further research is needed to understand the clinical impact of this comorbidity.

The Alice in Wonderland syndrome

The Alice in Wonderland syndrome is a term applied to altered bizarre perceptions of size and shapes of a patient's body and illusions of changes in the forms, dimensions, and motions of objects that a patient with this syndrome encounters. These metamorphopsias arise during complex partial seizures, migraine headaches, infections, and intoxications. The illusions and hallucinations resemble the strange phenomena that Alice experienced in Lewis Carroll's Alice's Adventures in Wonderland. Charles Lutwidge Dodgson, whose nom de plume was Lewis Carroll, experienced metamorphopsias. He described them in the story that he wrote for Alice Liddell and her two sisters after he spun a tale about a long and strange dream that the fictional Alice had on a warm summer day. The author of this chapter suggests that Dodgson suffered from migraine headaches and used these experiences to weave an amusing tale for Alice Liddell. The chapter also discusses the neurology of mercury poisoning affecting the behavior of Mad Hatter character. The author suggests that the ever-somnolent Dormouse suffered from excessive daytime sleepiness due to obstructive sleep apnea.

Acute, subacute and long-term subjective effects of psilocybin in healthy humans: a pooled analysis of experimental studies

Psilocybin and related hallucinogenic compounds are increasingly used in human research. However, due to limited information about potential subjective side effects, the controlled medical use of these compounds has remained controversial. We therefore analysed acute, short- and long-term subjective effects of psilocybin in healthy humans by pooling raw data from eight double-blind placebo-controlled experimental studies conducted between 1999 and 2008. The analysis included 110 healthy subjects who had received 1-4 oral doses of psilocybin (45-315 µg/kg body weight). Although psilocybin dose-dependently induced profound changes in mood, perception, thought and self-experience, most subjects described the experience as pleasurable, enriching and non-threatening. Acute adverse drug reactions, characterized by strong dysphoria and/or anxiety/panic, occurred only in the two highest dose conditions in a relatively small proportion of subjects. All acute adverse drug reactions were successfully managed by providing interpersonal support and did not need psychopharmacological intervention. Follow-up questionnaires indicated no subsequent drug abuse, persisting perception disorders, prolonged psychosis or other long-term impairment of functioning in any of our subjects. The results suggest that the administration of moderate doses of psilocybin to healthy, high-functioning and well-prepared subjects in the context of a carefully monitored research environment is associated with an acceptable level of risk.

Human hallucinogen research: guidelines for safety

There has recently been a renewal of human research with classical hallucinogens (psychedelics). This paper first briefly discusses the unique history of human hallucinogen research, and then reviews the risks of hallucinogen administration and safeguards for minimizing these risks. Although hallucinogens are relatively safe physiologically and are not considered drugs of dependence, their administration involves unique psychological risks. The most likely risk is overwhelming distress during drug action ('bad trip'), which could lead to potentially dangerous behaviour such as leaving the study site. Less common are prolonged psychoses triggered by hallucinogens. Safeguards against these risks include the exclusion of volunteers with personal or family history of psychotic disorders or other severe psychiatric disorders, establishing trust and rapport between session monitors and volunteer before the session, careful volunteer preparation, a safe physical session environment and interpersonal support from at least two study monitors during the session. Investigators should probe for the relatively rare hallucinogen persisting perception disorder in follow-up contact. Persisting adverse reactions are rare when research is conducted along these guidelines. Incautious research may jeopardize participant safety and future research. However, carefully conducted research may inform the treatment of psychiatric disorders, and may lead to advances in basic science.

Indolealkylamines: biotransformations and potential drug-drug interactions

Indolealkylamine (IAA) drugs are 5-hydroxytryptamine (5-HT or serotonin) analogs that mainly act on the serotonin system. Some IAAs are clinically utilized for antimigraine therapy, whereas other substances are notable as drugs of abuse. In the clinical evaluation of antimigraine triptan drugs, studies on their biotransformations and pharmacokinetics would facilitate the understanding and prevention of unwanted drug-drug interactions (DDIs). A stable, principal metabolite of an IAA drug of abuse could serve as a useful biomarker in assessing intoxication of the IAA substance. Studies on the metabolism of IAA drugs of abuse including lysergic acid amides, tryptamine derivatives and beta-carbolines are therefore emerging. An important role for polymorphic cytochrome P450 2D6 (CYP2D6) in the metabolism of IAA drugs of abuse has been revealed by recent studies, suggesting that variations in IAA metabolism, pharmaco- or toxicokinetics and dynamics can arise from distinct CYP2D6 status, and CYP2D6 polymorphism may represent an additional risk factor in the use of these IAA drugs. Furthermore, DDIs with IAA agents could occur additively at the pharmaco/toxicokinetic and dynamic levels, leading to severe or even fatal serotonin toxicity. In this review, the metabolism and potential DDIs of these therapeutic and abused IAA drugs are described.

Antipsychotic drug treatment of schizophrenic patients with substance abuse disorders

BACKGROUND/AIM

In recent years, there has been a growing interest in developing adequate treatments for patients with a diagnosis of schizophrenia and a comorbid substance use disorder (SUD). In the present paper we aim to critically review published reports on the use of conventional and second-generation antipsychotics in the treatment of patients with schizophrenia and comorbid SUD, to provide clinicians with a clearer view of the pharmacological treatment of this highly prevalent dual diagnosis based upon the evidence arising from the scientific literature.

METHODS

A search of the relevant literature from Medline, PsycLIT and EMBASE databases, included in the Science Citation Index, and available up to November 2006 was conducted using the terms: 'schizophrenia', 'substance use disorder' and 'antipsychotics'.

RESULTS

While research on the use of conventional antipsychotics has remained limited, the majority of studies suggest the effectiveness of second-generation antipsychotics, particularly clozapine, for patients with schizophrenia and a comorbid substance use disorder.

CONCLUSION

In the absence of randomized controlled trials that could provide more reliable information, clinical decisions may need to rely on indirect data provided by the increasing number of case reports, open trials and retrospective studies showing a decrease in cigarette smoking, alcohol, cocaine or cannabis use and an improvement of overall psychiatric symptoms.

Clonazepam treatment of lysergic acid diethylamide-induced hallucinogen persisting perception disorder with anxiety features

An unique and intriguing characteristic of lysergic acid diethylamide (LSD) and LSD-like substances is the recurrence of some of the symptoms which appear during the intoxication, in the absence of recent intake of hallucinogens. Hallucinogen persisting perception disorder (HPPD) is a condition in which the re-experiencing of one or more perceptual symptoms causes significant distress or impairment in social, occupational or other important areas of functioning and may be extremely debilitating. Benzodiazepines are one of the recommended agents for the treatment of HPPD but it is unclear which of them may be more helpful. The goal of our investigation was to assess the efficacy of clonazepam in the treatment of LSD-induced HPPD. Sixteen patients fulfilled entrance criteria. All complained of HPPD with anxiety features for at least 3 months and were drug free at least 3 months. They received clonazepam 2 mg/day for 2 months. Follow-up was continued for 6 months. They were weekly evaluated during the 2 months of clonazepam administration and monthly during the follow-up period using the Clinical Global Impression Scale, a Self-report Scale and Hamilton Anxiety Rating Scale. Patients reported a significant relief and the presence of only mild symptomatology during the clonazepam administration. This improvement was clearly sustained and persisted during a 6-month follow-up period. This study suggests that high potency benzodiazepines like clonazepam, which has serotonergic properties, may be more effective than low-potency benzodiazepines in the treatment of some patients with LSD-induced HPPD.

Do hallucinogens cause residual neuropsychological toxicity?

We collected and reviewed studies in which neuropsychological tests were administered to users of LSD or other hallucinogens. Interpretation of the studies is limited by various confounding variables, such as subjects' premorbid cognitive and personality function and prior use of other substances. At present, the literature tentatively suggests that there are few, if any, long-term neuropsychological deficits attributable to hallucinogen use. To better resolve this issue, however, it will be important to study larger samples of chronic, frequent hallucinogen users who have not often used other types of drugs.