Psychedelics and Anxiety

Psychedelics and anxiety is one of the 'psychedelics and ...' topics that we're currently making a page for. At this moment you can find all papers (in our database) on this topic below.

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Our vision is that psychedelics can be used worldwide to better the lives of as many as 450 million people who suffer from mental health problems. Our information hopes to make that vision come to life just a little faster.

Anxiety Research

Here will be a narrative, readable, summary of the research.


In our literature study we came across the following studies of note. Browse the meta, review, commentary articles for an overview. Check out the individual studies for specific experiments and observations.

Psilocybin for End-of-Life Anxiety Symptoms: A Systematic Review and Meta-Analysis

2021 | Hsu, C., Li, D., Liang, C., Stubbs, B., Tseng, P., Yang, F., Yang, S., Yeh, T., Yu, C.

This review paper (2021) provides further evidence for the use of psilocybin-assisted therapy for the treatment of end-of-life anxiety in the absence of serious adverse effects.

Assessing the effects of methodological differences on outcomes in the use of psychedelics in the treatment of anxiety and depressive disorders: A systematic review and meta-analysis

2021 | Lang, R. F., Leger, R. F., Unterwald, E. M.

This review paper (2021) explored the type of psychedelics used across a number of studies and the number of dosing sessions administered that affect subjects’ depression and anxiety outcomes and adverse drug reactions. The authors conclude that psilocybin, ayahuasca & DMT all appear to be effective and safe in improving symptoms of anxiety and depression.

The Viability of Microdosing Psychedelics as a Strategy to Enhance Cognition and Well-being – An Early Review

2019 | Bornemann, J.

This 2019 review examines the viability of microdosing psychedelics as a method to improve cognition and well-being. Available evidence indicates a variety of benefits including improvements in mood, focus, and creativity, with some people experiencing no discernible effects or expressing concerns about selective negative consequences like increased anxiety, however, most insights stem from observational studies using convenience samples that are biased or unrepresentative of the general population.

Psilocybin-Assisted Therapy: A Review of a Novel Treatment for Psychiatric Disorders

2017 | Lastra, D., Malcolm, B., Thomas, K.

This 2017 review examines studies on psilocybin-assisted therapy to treat psychiatric disorders related to depression, anxiety, and substance abuse. In contrast to conventional paradigms, psilocybin-assisted therapy consists of only a few six-hour medication therapy sessions that may significantly improve symptoms and help patients achieve response or remission within weeks with support from integrative psychotherapy sessions.

Psychedelic Psychiatry’s Brave New World

2020 | Carhart-Harris, R. L., Erritzoe, D., Nutt, D. J.

This popular commentary article (2020) describes the current resurrection of research into psychedelics (both neuroscience and therapeutic applications). It describes the evidence for the serotonin receptor (5-HT2a) agonism (psychedelics binding to that receptor) and the possible mechanisms through which long-lasting therapeutic effects can be found.

Novel pharmacological targets in drug development for the treatment of anxiety and anxiety-related disorders

2019 | Sartori, S. B., Singewald, N.

This review (2019) investigates psychedelics (and other medications) as promising treatments for anxiety and anxiety-related disorders. In combination with talk or exposure therapy, these new drugs can increase the effectiveness of treatments.

Natural Psychoplastogens As Antidepressant Agents

2020 | Benko, J., Vranková, S.

This review (2020) explored recent advances in natural psychoplastogens (psychedelics) as antidepressant agents. The study noted that these compounds are effective in rapid structural and functional rearrangement of neural systems by targeting mechanisms that were previously implicated in the development of depression. The study observed the evidence that they expend potent acute and long-term positive effects, beyond the treatment of psychiatric disorders with many of them being naturally occurring compounds, like psilocybin and DMT.

Embedding existential psychology within psychedelic science: reduced death anxiety as a mediator of the therapeutic effects of psychedelics.

2019 | Arena, A. F., Menzies, R. E., Moreton, S. G., Szalla, L.

The hypothesis paper (2019) reviewed the psychological mechanisms through which psychedelics can improve psychological well-being and proposes that reducing death anxiety is a key mechanism. The review called for linking existential psychology with psychedelic science so that an awareness of the role of death anxiety in psychopathology can help guide more research into psychedelic therapies in the future.

Psychedelic-Assisted Group Therapy: A Systematic Review

2019 | Anderson, B. T., Glick, G., Hooker, A. R., Stauffer, C., Trope, A., Woolley, J. D.

This review (2019) investigates what research has been done with psychedelic-assisted group therapy. It identifies 12 studies, mostly with LSD (2 with psilocybin), and ranging from surveys to randomized controlled trials.

Registered clinical studies investigating psychedelic drugs for psychiatric disorders

2021 | Gill, H., Lipsitz, O., Lui, L. M. W., McIntyre, R. S., Rosenblat, J. D., Siegel, A. N., Teopiz, K. M.

This review (2021) summarizes the study characteristics of all ongoing registered clinical trials investigating psychedelic drugs for psychiatric disorders and identifies that their majority focuses on investigating MDMA and psilocybin for treating depression or PTSD, while only 30% of their results are published.

Dark Classics in Chemical Neuroscience: 3,4-Methylenedioxymethamphetamine

2018 | Andrews, A. M., Dunlap, L. E., Olsen, D. E.

This review (2018) examines the synthesis of MDMA as well as its pharmacology, metabolism, adverse effects, and potential use in medicine.

Production Options for Psilocybin: Making of the Magic

2018 | Blei, F., Fricke, J., Hoffmeister, D., Lenz, C., Wick, J.

This historic review (2019) examines the biosynthesis and pharmacology of psilocybin, and summarizes the biotechnological routes of its synthesis.

The Use of Salvia divinorum from a Mazatec Perspective

2018 | Maqueda, A. E.

This book chapter (2018) investigates the use of salvia divinorum by the Mazatec people. Applications discussed include headaches (pain), inflammation, addiction, and depression. Next to medicinal and psychotherapeutic applications, the inner exploration (recreational) purposes are also discussed.

Psychedelic Drugs in Biomedicine

2017 | Gainetdinov, R. R., Kalueff, A. V., Kyzar, E. J., Nichols, C. D., Nichols, D. E.

This review (2017) summarizes pre/clinical data pertaining to the effects of psychedelics and their pharmacological mechanisms of action and outlines future areas of translational research to investigate how synapse-related gene expression influences the disruption of established neural connectivity patterns, underlying therapeutic effects.

How could MDMA (ecstasy) help anxiety disorders? A neurobiological rationale

2009 | Johansen, P. Ø., Krebs, T. S.

This paper (2009) suggests three potential mechanisms for the efficacy of MDMA as a treatment for anxiety disorders. These mechanisms are linked to oxytocin levels, amygdala and vmPFC activity, and norepinephrine and cortisol release.

The psychedelic mystical experience in the human encounter with death

1971 | Pahnke, W. N.

This early review (1969) investigates the mystical experience and its relationship to death, with a focus on terminal cancer patients who had received psychedelics at that time. The correlation between the profoundness of the experience and therapeutic (long-term/non-acute) outcomes is also discussed.

Psilocybin in end of life care: Implications for further research

2021 | Summergrad, P.

This commentary (2016) examines the study design and the outcome measures of two randomized controlled studies that used psilocybin to treat mood and anxiety in patients undergoing palliative care. It can be concluded that the experiences of salience, meaningfulness, and healing that accompany the powerful spiritual experiences elicited by psilocybin, mediate the antidepressant and anxiolytic outcomes measures. Future investigations may investigate these phenomena in their own right, as well as replicate these findings in diverse clinical populations that aim to implement more robust blinding measures.

Clinical and biological predictors of psychedelic response in the treatment of psychiatric and addictive disorders: a systematic review

2021 | Benyamina, A., Hermand, M., Karila, L., Pétillion, A., Romeo, B.

This systematic review (2021) of studies from 1990 to 2020 aimed to determine factors that can predict successful response to psychedelic treatment. In a variety of disorders, the authors found that the intensity of the experience was the best such predictor.

Lysergic acid diethylamide: a drug of ‘use’?

2016 | Barnwal, P., Das, S., Mondal, S., Ramasamy, A., Sen, S.

This review (2016) provides a chronologic history of LSD and examines its safety profile, the potential for abuse, its therapeutic potential to treat alcoholism or terminally ill patients. It also summarizes insights about its receptor pharmacology, mechanism of action, and (adverse) effects, while highlighting some of its potential clinical applications such as an antianxiety agent, a creativity enhancer, a suggestibility enhancer, or a performance enhancer.

Historic psychedelic drug trials and the treatment of anxiety disorders

2020 | Bird, C. I. V., Daniel, A., Gibbs, D., Goldsmith, D., Jelen, L. A., Knight, G., Rucker, J., Weston, N. M., Young, A. H.

This meta-review (2019) examined the efficacy of psychedelics combined with therapy for the treatment of anxiety disorders, across twenty studies conducted between 1940 to 2000. The review outlines individual aspects of their design, assessment methodology, and notable shortcomings, such as the lack of randomized control designs and overreliance on the therapists' opinion. The large majority of patients of these studies exhibited improved symptoms over the course of treatment with psychedelic-assisted therapy.

Integrating psychotherapy and psychopharmacology: psychedelic-assisted psychotherapy and other combined treatments

2020 | Feduccia, A. A., Garel, N., Greenway, K. T., Jerome, L.

This meta-review (2020) examines the therapeutic frameworks surrounding contemporary practices of psychedelic-assisted psychotherapy, with regard to the historic development of therapeutic models and contemporary insights into extra-pharmacological factors and underlying mechanisms. They highlight that these therapies entail greater environmental sensitivity from the patient's perspective, which requires more meticulous attention for the preparation of the set and setting, a considerably resource-intensive endeavor.

From Hofmann to the Haight Ashbury, and into the Future: The Past and Potential of Lysergic Acid Diethlyamide

2014 | Dickerson Davidson, L., Raswyck, G. E., Smith, D. E.

This review (2014) summarises the history of LSD research and outlines the potential applications in the future.

Potential Therapeutic Effects of Psilocybin

2017 | Griffiths, R. R., Johnson, M. W.

This review (2017) evaluates the therapeutic research into psilocybin as a treatment for addiction, treatment-resistant depression, and mood and anxiety disorders. The authors also analyse the safety data from these clinical trials.

Psychedelics and Psychedelic-Assisted Psychotherapy

2020 | Carpenter, L. L., Kalin, N. H., McDonald, W., Nemeroff, C. B., Reiff, C. M., Richman, E. E., Rodriguez, C. I., Widge, A. S.

This review (2020) finds that randomized clinical trials (RCTs) support the efficacy of various psychedelic-assisted therapies for mental health disorders.

Psychedelics and dying care: A historical look at the relationship between psychedelics and palliative care

2019 | Dyck, E.

This review article (2019) retraces the history of psychedelics (specifically LSD) for palliative care and the possibility of reducing (end-of-life) anxiety.

The Emerging Role of Psilocybin and MDMA in the Treatment of Mental Illness

2020 | Cha, D. S., Chen-Li, D., El-Halabi, S., Gill, B., Gill, H., Ho, R., Lee, Y., Lipsitz, O., Majeed, A., Mansur, R. B., McIntyre, R. S., Nasri, F., Rodrigues, N. B., Rosenblat, J. D.

This narrative review (2020) evaluates the therapeutic potential of psilocybin and MDMA for the treatment of major depressive disorder (MDD), post-traumatic stress disorder (PTSD), and anxiety. The review explains the need for effective mental health treatments and highlights the lack of dose-response studies in placebo-controlled settings with a real-world clinical population.

Modern clinical research on LSD

2017 | Liechti, M. E.

This review (2017) presents the findings from all six clinical studies using LSD in the previous 25 years, detailing the effects and suggested mechanism of action in both healthy participants, and those with end-of-life anxiety.

Serotonergic hallucinogens in the treatment of anxiety and depression in patients suffering from a life-threatening disease: A systematic review

2018 | Gasser, P., Gutwinski, S., Hermle, L., Jungaberle, H., Majic, T., Reiche, S.

This systematic review (2018) of 11 clinical trials (n=445) found that psychedelics (LSD, psilocybin) reduced symptoms of depression and anxiety in patients with life-threatening diseases (end-of-life).

Therapeutic effects of classic serotonergic psychedelics: A systematic review of modern-era clinical studies

2020 | Andersen, K. A. A., Carhart-Harris, R. L., Erritzoe, D., Nutt, D. J.

This systematic review (2020) looked at 10 modern studies (n=188) on psychedelics (psilocybin, ayahuasca, LSD) for the treatment of a variety of mental health disorders. The review found the studies to provide evidence for efficacy (up to months later) and safety.

MDMA-assisted therapy: A new treatment model for social anxiety in autistic adults

2016 | Danforth, A. L., Grob, C. S., Struble, C., Yazar-Klosinski, B.

This overview/review paper lays the groundwork for offering MDMA-assisted psychotherapy for the treatment of social anxiety in autistic adults.

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

2016 | Crippa, J. A., Dos Santos, R. G., Hallak, J. E., Osório, F. L.

A systematic review (2016) found that psychedelics (serotonergic 'hallucinogens') have a distinct influence on brain structures that have anxiolytic (anxiety-relieving), antidepressant, and antiaddictive properties.

The experimental effects of psilocybin on symptoms of anxiety and depression: A meta-analysis

2020 | Goldberg, S. B., Hutson, P. R., Nicholas, C. R., Pace, B. T., Raison, C. L.

This meta-analysis (2020) reported favorably on four trials (n=117) that studied the effect of psilocybin-assisted therapy for anxiety and depression.

A Meta-Analysis of Placebo-Controlled Trials of Psychedelic-Assisted Therapy

2020 | Bathje, G. J., Chwyl, C., Davis, A. K., Lancelotta, R., Luoma, J. B.

This meta-analysis of nine placebo-controlled trials (n=211) showed a very large effect size (g=1.21) of treatment on four mental health conditions (PTSD, end-of-life anxiety, depression, social anxiety among autistic adults).

MDMA-Assisted Therapy as a Means to Alter Affective, Cognitive, Behavioral, and Neurological Systems Underlying Social Dysfunction in Social Anxiety Disorder

2021| Lear, M. K., Luoma, J. B.

This review (2021) explores the potential of MDMA-assisted therapy for treating the various symptoms of social anxiety disorder (SAD). The authors hypothesize how disruptions in neurological, perceptual, receptive, and expressive systems regulating social behavior in SAD may take place as a result of MDMA-assisted therapy, thereby acting as a stimulus for further research.

Psychedelic mushrooms in the USA: Knowledge, patterns of use and association with health outcomes

2021| Lerer, B., Lerer, L. B., Matzopoulos, R., Morlock, A., Morlock, R.

This preprint survey study (n=7139) assessed the use of psychedelic mushrooms amongst adults in the US. The survey found that people generally self medicate with psychedelic mushrooms for reasons related to mental health, with users reporting significantly higher levels of anxiety and depression. The study concludes with a call for a use-related harm reduction strategy for psychedelic mushrooms in the US.

Persisting effects of ayahuasca on empathy, creative thinking, decentering, personality, and well-being

2021| Kiraga, M. K., Kuypers, K. P. C., Mason, N. L., Ramaekers, J. G., Toennes, S. W., Uthaug, M. V., van Oorsouw, K.

This provisionally accepted study (n=40) explored the effects of ayahuasca on processes involved in stress-related psychopathologies. Volunteers attending an ayahuasca ceremony were given a series of questionnaires at baseline, the morning after and one week after the experience. Researchers found ingesting ayahuasca is associated with positive therapeutic outcomes.

Sub-acute and long-term effects of ayahuasca on mental health and well-being in healthy ceremony attendants: A replication study

2021| Broers, N. J., Mason, N. L., Ramaekers, J. G., Uthaug, M. V., van Oorsouw, K.

This observational study (n=73) replicated an earlier ayahuasca ceremony study, but this time found only improvements in self-reported stress four weeks later, no reduction in depression was observed. The study did also replicate findings of increased life satisfaction the day after the ceremony, which returned to baseline four weeks after.

Psychedelic drug use and schizotypy in young adults

2021| Åberg, A., Acar, K., Almeida, R., Atlas, L., Garzón, B., Ingvar, M., Lebedev, A. V., Louzolo, A., Lövdén, M., Martinsson, S., Olsson, A., Pärnamets, P., Petrovic, P., Råback, J.

This observational survey (n=1032) and experimental (n=39) study investigated the relationship between psychedelic drug use and schizotypal behavior and personality trait. Results indicate that psychedelics do not pose serious risks for developing psychotic symptoms in healthy young adults, in fact, psychedelic drug exposure was associated with better evidence integration, less bias against disconfirmatory evidence, and more flexible aversive learning, compared to psychos-like behaviors that were more commonly associated with psychostimulant use.

Psychedelics not linked to mental health problems or suicidal behavior: A population study

2015| Johansen, P. Ø., Krebs, T. S.

This 2015 observational survey study (n=135 095) investigated the association between lifetime psychedelic use (LSD, psilocybin, mescaline) and mental health problems, but found no indication of increased likelihood for psychological distress, mental health treatment, suicidal behavior, depression, or anxiety amongst psychedelic users (n=19 299). These results contest the justification for prohibiting psychedelics as a public health measure.

The effect of esketamine in patients with treatment-resistant depression with and without comorbid anxiety symptoms or disorder

2021| Borentain, S., Daly, E. J., Fedgchin, M., Ionescu, D. F., Salvadore, G., Singh, J. B., Starr, H. L., Thase, M., Trivedi, M. H., Turkoz, I.

This post-approval, double-blind, placebo-controlled study (n=223, TRANSFORM-2) finds that those with comorbid anxiety (72%) responded just as well as those without anxiety to esketamine (56-84mg, 4 weeks, combined with SSRI) treatment.

MDMA does not alter responses to the Trier Social Stress Test in humans

2017| Bershad, A. K., de Wit, H., Miller, M. A.

This randomized, double-blind, placebo-controlled, between-subjects study (n=39) assessed the effects of MDMA (35mg and 70mg/70kg) or placebo on physiological and subjective responses to a public speaking task under stressful and non-stressful conditions. Contrary to their initial hypothesis of dampening stress reactions, MDMA produced stress-like effects on both physiological (heart rate, blood pressure, cortisol) and subjective (ratings of stress, tension, and insecurity) ratings on both the stress and no-stress sessions.

Using Psychedelics With Therapeutic Intent Is Associated With Lower Shame and Complex Trauma Symptoms in Adults With Histories of Child Maltreatment

2021| Healy, C. J., Lee, K. A.

This survey study (n=166) investigates whether psychedelic use moderates the relationships between child maltreatment, self-concept, social cognition, and posttraumatic stress symptoms. Results indicate that using psychedelic drugs with therapeutic intent is associated with lower levels of complex posttraumatic stress symptoms and internalized shame in individuals with histories of child maltreatment.

Exploring the Use of Psilocybin Therapy for Existential Distress: A Qualitative Study of Palliative Care Provider Perceptions

2021| Acquaviva, K. D., LeBaron, V. T., Mayer, C. E.

This qualitative interview study (n=5) examines the attitudes of palliative care workers towards the use of psilocybin therapy for death anxiety and identified common themes concerning the perceived barriers of treating existential distress and their uncertainty about the risks and benefits of psilocybin.

Direct comparison of the acute subjective, emotional, autonomic, and endocrine effects of MDMA, methylphenidate, and modafinil in healthy subjects

2017| Borgwardt, S., Dolder, P. C., Müller, F., Schmid, Y.

This placebo-controlled, double-blind, cross-over study (n=24) compared the acute autonomic, subjective, endocrine, and emotional effects of single doses of MDMA (125 mg), methylphenidate (60 mg), modafinil (600 mg) in healthy subjects using psychometric scales, the Facial Emotion Recognition Task (FERT), and the Sexual Arousal and Desire Inventory (SADI). It found that while all active drugs induced comparable hemodynamic and adverse effects, MDMA induced subjective, emotional, sexual, and endocrine effects that were distinctive from those of methylphenidate and modafinil with the doses used.

Distinct acute effects of LSD, MDMA, and D-amphetamine in healthy subjects

2019| Borgwardt, S., Duerig, R., Eckert, A., Holze, F., Ley, L., Liechti, M. E., Müller, F., Varghese, N., Vizeli, P.

This placebo-controlled, randomized, double-blind, cross-over study (n=28) investigated distinct acute autonomic, subjective, and endocrine effects of single doses of LSD (0.1 mg), MDMA (125 mg), D-amphetamine (40 mg) in healthy subjects. The results show that LSD, MDMA and D-amphetamine had different ratings on the 5 Dimensions of Altered States of Consciousness scale (5DASC) and Mystical Experience Questionnaire (MEQ). It also clearly indicates the distinct neurological and behavioral profiles of LSD, MDMA and D-amphetamine.

Real-world effectiveness of repeated ketamine infusions for treatment resistant depression during the COVID-19 pandemic

2021| Di Vincenzo, J. D., Kratiuk, K., Lee, Y., Lipsitz, O., McIntyre, R. S., Rodrigues, N. B., Rosenblat, J. D., Subramaniapillai, M.

This open-label study (n=267) investigated if Covid had any impact on the effectiveness of ketamine treatments (iv, 4x 35-53mg/70kg) for depression (TRD). Patients in both groups experience significant and comparable improvements in depressive symptoms, suicidal ideation (SI), and anxiety.

Ketamine’s dose-related effects on anxiety symptoms in patients with treatment refractory anxiety disorders

2017| Anderson-Fahey, B., Glue, P., Gray, A., Harland, S., Le Nedelec, M., McNaughton, N., Medlicott, N. J., Neehoff, S.

This ascending single-dose study (n=12) evaluates the dose-related effects of ketamine (18-70mg/70kg) on patients with anxiety symptoms with treatment-resistant anxiety disorders. Ten of the twelve participants (83%) found relief for up to seven days. The results support ketamine as a potential therapeutic alternative for patients with anxiety disorders.

Noribogaine is a G-Protein Biased κ-Opioid Receptor Agonist

2015| Fishback, J., Garamszegi, N., Heghinian, M. D., Maillet, E. L., Mash, D. C., Milon, N., Schürer, S. C.

This study examines the specific roles and activities of noribogaine at the opioid receptors in relation to physiological outputs in order to characterize noribogaine to the mu (OPRM) and the kappa (OPRK) opioid receptors. The study observed that the biased agonist/antagonist pharmacology is distinctive to noribogaine in comparison to other ligands including ibogaine, nalmefene, 18-MC, and 6′-GNTI. It predicted that noribogaine promoted some analgesic effects and anti-addictive response.

Prospective examination of synthetic 5-methoxy-N,N-dimethyltryptamine inhalation: effects on salivary IL-6, cortisol levels, affect, and non-judgment

2019| Davis, A. K., Lancelotta, R., Ramaekers, J. G., Riba, J., Szabo, A., Uthaug, M. V.

This naturalistic observational study (n=11) of 5-MeO-DMT inhalation on biomarkers, immune functions and mindfulness, depression, stress, and anxiety found that 5-MeO-DMT substantially increased cortisol ratings and reduced IL-6 concentrations in saliva. The said changes were not liked to ratings of mental health or the psychedelic experience. Ratings of non-judgment considerably increased, while depression, anxiety and stress ratings decreased.

Ayahuasca Improves Self-perception of Speech Performance in Subjects With Social Anxiety Disorder: A Pilot, Proof-of-Concept, Randomized, Placebo-Controlled Trial

2021| Bouso, J. C., Dos Santos, R. G., Hallak, J. E., Osório, F. L., Rocha, J. M., Rodrigues, L. S., Rossi, G. N., Silveira, G., Yonamine, M.

This randomized placebo-controlled, proof-of-concept pilot study (n=17) investigated the effects of ayahuasca on individuals with social anxiety and found that it improved their self-perception of speech performance independent of task-related anxiety or alterations in their recognition of emotional facial expressions.

Might Microdosing Psychedelics Be Safe and Beneficial? An Initial Exploration

2019| Fadiman, J., Korb, S.

This diary study investigates the "safe and beneficial" use of psychedelics in small quantities (microdosing; 10 micrograms LSD) to improve positive moods by evaluating positive and negative emotional states using the PANAS checklist and written reports. The study showed that microdosing of a psychedelic in clinical and non-clinical populations improved health habits, increased energy, and improved work effectiveness. Furthermore, smaller samples demonstrated alleviation of symptoms in migraine headaches, traumatic brain injury, pre-menstrual syndromes (PMS), shingles, and other such conditions that have not been previously associated with psychedelic use.

Microdosing psychedelics: Demographics, practices, and psychiatric comorbidities.

2020| Anderson, T., Dinh-Williams, L., Hapke, E., Hui, K., Petranker, R., Rosenbaum, D., Weissman, C. R.

This survey (n=909) of psychedelic microdosers founds that they were more likely, than the general public, to have used substances recreational, were less likely to suffer from substance use disorder (SUD), or anxiety disorder. Most microdosed with either LSD (13μg) or psilocybin (0.3g).

Efficacy of intravenous ketamine treatment in anxious versus nonanxious unipolar treatment‐resistant depression

2018| Cusin, C., Debattista, C., Fava, M., Flynn, M., Freeman, M. P., Hock, R. S., Hoeppner, B., Ionescu, D. F., Iosifescu, D. V., Mathew, S. J., Papakostas, G. I., Salloum, N. C., Sanacora, G., Trivedi, M. H.

This multisite, double-blind, placebo-controlled study (n=99) evaluated the effect of ketamine (3.5 - 35 mg/70kg) versus midazolam (3.15 mg/70kg) in anxious versus non-anxious unipolar treatment‐resistant depression (TRD). The pilot results concluded that there was no significant effect found between both groups. In contrast to traditional antidepressants, the effects of ketamine may be similar in both anxious and non-anxious TRD subjects.

Anxiety, panic, and hopelessness during and after ritual ayahuasca intake in a woman with generalized anxiety disorder: A case report

2017| Crippa, J. A., Dos Santos, R. G., Hallak, J. E., Osório, F. L.

This case report (n=1) describes a woman with generalized anxiety disorder who experienced extreme anxiety, panic, and hopelessness during and up to three days after taking ayahuasca. This is the first description of a prolonged 'bad' trip in the literature.

Chronic, Intermittent Microdoses of the Psychedelic N, N-Dimethyltryptamine (DMT) Produce Positive Effects on Mood and Anxiety in Rodents

2019| Benson, C. J., Cameron, L. P., DeFelice, B. C., Fiehn, O., Olson, D. E.

This animal study (n=35) investigated the effects of microdosing DMT (1mg/kg) in rats and found that a chronic (∼2 months), intermittent (every third day) microdosing regimen facilitated fear extinction learning and reduced depressive immobility in the forced swim test without producing the anxiety-like effects characteristic of a high dose.

Self-Rated Effectiveness of Microdosing With Psychedelics for Mental and Physical Health Problems Among Microdosers

2019| Dolder, P. C., Hutten, N. P. W., Kuypers, K. P. C., Mason, N. L.

This survey study (n=410) showed that those with mental & physical health problems self-rated the effectiveness of microdosing as higher than conventional treatments in regards to ADHD/ADD and anxiety. They rated it as less effective than a high dose of psychedelics.

Ceremonial Ayahuasca in Amazonian Retreats—Mental Health and Epigenetic Outcomes From a Six-Month Naturalistic Study

2021| Butler, M., Davies, M., Dempster, E. L., Morgan, C. J. A., Netzband, N., Rucker, J., Ruffell, S. G. D., Tsang, WF., Tófoli, L.F., Young, A. H.

This open-label (naturalistic) study (n=63) found that participants in ayahuasca retreats improved in scores of mental health (depression, anxiety, self-compassion), these effects lasted and were even somewhat improved at the 6-month follow-up. A study of participant's epigenetic data didn't yield conclusive results.

Possible Interactions Between 5-HT2A Receptors and the Endocannabinoid System in Humans: Preliminary Evidence of Interactive Effects of Ayahuasca and Endocannabinoids in a Healthy Human Subject

2018| Crippa, J. A., Dos Santos, R. G., Hallak, J. E., Marchioni, C., Osório, F. L., Queiroz, M. E. C., Rocha, J. M., Rossi, G. N., Silveira, G., Yonamine, M.

This open-label case study (n=1) investigated the effects of a single oral dose of ayahuasca (49.14mg DMT, 124.88mg harmine,54.6mg tetrahydroharmine, and 2.73mg harmaline /70kg) and observed a continuous decrease in the plasma level of the endocannabinoid anandamide and late-stage increase of the endocannabinoid 2-arachidonoylglycerol.

Effects of N, N-Dimethyltryptamine on Rat Behaviors Relevant to Anxiety and Depression

2018| Benson, C. J., Cameron, L. P., Dunlap, L. E.

This study in rats with DMT found that it reduced anxiety by extinguishing of cued fear memory and reduces immobility in the forced swim test (a proxy for depression).

Embracing Neurodiversity in Psychedelic Science: A Mixed-Methods Inquiry into the MDMA Experiences of Autistic Adults

2019| Danforth, A. L.

This retrospective survey (n=100) and qualitative interview (n=24) study examined the MDMA experiences of autistic adults and identified that many of them viewed MDMA as a transformative healing catalyst for helping their anxieties of navigating through neurotypical social norms, while none of them expressed the desire for being neurotypical or reported being "cured" from autism.

Cross-sectional associations between lifetime use of psychedelic drugs and psychometric measures during the COVID-19 confinement: A transcultural study

2021| Alcázar-Córcoles, M. A., Bouso, J. C., Dos Santos, R. G., Hallak, J. E., Ona, G., Révész, D., Rocha, J. M., Rossi, G. N.

This survey study (n=2,974) investigated the relationship between lifetime psychedelic use, personality traits, and mental health during the COVID-19 confinement, and found that regular use was associated with less psychological distress, less peritraumatic stress, and more social support. Psychedelic drug users also scored higher on the novelty-seeking and self-transcendence scales, but lower on cooperativeness.

An analog of psychedelics restores functional neural circuits disrupted by unpredictable stress

2021| Cameron, L. P., Cao, B., Chen, L., Lu, J., Lukasiewicz, K., Mullen, B., Olson, D. E., Shah-Morales, S., Tjia, M., Weiser, S., Zuo, Y.

This animal study (n=76) tested the rescue effects of a single dose of the ibogaine-analog tabernanthalog (10 mg/kg) administered after mild exposure to unpredictable mild stress in mice and found that it restored deficits in dendritic spine structural dynamics, neuronal activities, and the bottom-up processing of novel contextual information.

Ketamine Effects on EEG during Therapy of Treatment-Resistant Generalized Anxiety and Social Anxiety

2018| Glue, P., Kawe, T., Martin, D., McNaughton, N., Neehoff, S., Shadli, S. M.

This randomized, double-blind, active placebo-controlled study (n=12) investigated the effects of 3 ascending ketamine dose levels (17.5, 35 & 70 mg/70kg) and midazolam (0.7mg/70kg) on electrophysiological brain activity in patients with anxiety. While ketamine increased high-frequency brain rhythms and decreased low-frequency rhythms in a dose-dependent manner, only decreases within the frontal theta frequency band were related to improvements in anxiety.

Psilocin and ketamine microdosing: effects of subchronic intermittent microdoses in the elevated plus-maze in male Wistar rats

2018| Horsley, R. R., Kolin, J., Páleníček, T., Valeš, K.

This placebo-controlled animal study (n=40) investigated the effects of ketamine (0.5 - 3 mg/kg) and psilocin (0.05 - 0.075 mg/kg) microdosing on anxiety-related explorative behavior in rats and found that both substances caused mild anxiety as measured by a reduction of explorative behavior on an elevated open surface.

Changes in self-rumination and self-compassion mediate the effect of psychedelic experiences on decreases in depression, anxiety, and stress

2021| Fauvel, B., Piolino, P., Strika-Bruneau, L.

This online survey study (n=164) investigated how psychedelic-induced mystical experiences improve depression, anxiety, and stress, and found that these effects are partially mediated through decreased self-rumination and increased self-compassion.

Psychedelic drug assisted psychotherapy in patients with terminal cancer

1972| Goodman, L. E., Grof, S., Kurland, A. A., Pahnke, W. N.

This early study (1972) describes the use of LSD-assisted psychotherapy for patients with terminal cancer. Results suggest significant improvements on various clinical assessments.

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

2003| Bleich, A., Gelkopf, M., Nachshon, H., Rudinski, D., Skladman, I.

This open-label study (n=16) suggests that high-potency benzodiazepines like clonazepam (2mg/day for 60 days) may be helpful in alleviating Hallucinogen Persisting Perception Disorder (HPPD). The patients reported relief up to four months after treatment. Do note that there was no control group in this study.

Effects of Long-Term Ayahuasca Administration on Memory and Anxiety in Rats

2015| Favaro, V. M., Oliveira, M. G. M., Soares, J. C. K., Yonamine, M.

This rodent study (2015) found that long-term administration of ayahuasca can interfere with the contextual association of emotional events in rats.

Lifetime use of psychedelics is associated with better mental health indicators during the COVID-19 pandemic

2021| Cavanna, F., Cuiule, J., Di Tella, R., González, P., Milano, V., Pallavicini, C., Tagliazucchi, E.

This survey (n=5618) found that those who used psychedelics (32% of the sample) had increased positive affect and more resilient personality traits (e.g. plasticity) during the COVID-19 pandemic.

Influence of Context and Setting on the Mental Health and Wellbeing Outcomes of Ayahuasca Drinkers: Results of a Large International Survey

2021| Bouso, J. C., Galvão-Coelho, N. L., Horák, M., Perkins, D., Sarris, J., Schubert, V., Simonová, H., Tófoli, L.F.

This survey (n=6877) of ayahuasca drinkers investigated the influence of context and setting on mental health and wellbeing outcomes. A combination of motivation, ceremony, and support variables predict these outcomes in a new model proposed in this paper.

A Qualitative Study of Intention and Impact of Ayahuasca Use by Westerners

2021| Bathje, G. J., Fenton, J., Hill, L. C., Pillersdorf, D.

This qualitative interview study (n=41) found that ayahuasca use by Westerners (in group settings), led to many sustained positive outcomes. These related to mental health, substance use, interpersonal relationships, and also creativity, physical health, connection to nature. Two participants indicated problematic experiences (sexual assault, enduring psychotic symptoms).

Clinical Studies of Lysergic Acid Diethylamide

1986| Anderson, E. W., Rawnsley, K.

This early clinical study (1954) investigated the dose-range effects of LSD (10-600μg) administered to patients and clinical staff (n=23) across 54 different research sessions and found that its effects entail highly potent perceptual alterations that are sensitive to the environment and variable across different individuals. They also note the emergence of phenomena such as enhanced sexual arousal and ego-dissolution and highlight its utility at illuminating basic personality structures but remain inconclusive as to whether it has therapeutic benefit in response to continued administration.

Antidepressant, anxiolytic and procognitive effects of subacute and chronic ketamine in the chronic mild stress model of depression

2017| Gruca, P., Lason-Tyburkiewicz, M., Papp, M., Willner, P.

This vehicle-controlled rodent study (n=16) compared the antidepressant and anxiolytic effects of ketamine (5, 10, 15 or 30 mg/kg) to the antidepressant imipramine (10 mg/kg), using chronic exposure to mild stress as a depression model and assessing their cognitive capacity of novel object recognition and their natural aversion to open spaces. Results indicated a sustained antidepressant-like effect of ketamine at an optimum dose of 10 mg/kg, which reversed the anxiogenic and dyscognitive effects of chronic mild stress exposure much faster than the classical antidepressant imipramine.

LSD-assisted psychotherapy and the human encounter with death

1972| Goodman, L. E., Grof, S., Kurland, A. A., Richards, W. A.

This early study (1972; n=31) on LSD-assisted psychotherapy (200-500µg) showed the promise of using psychedelics in combination with therapy. The participants of the study were diagnosed with cancer and received therapy/preparation before (10 hours) and after (1-2 hours). Of these patients, 9 (29%) significantly improved on scores of emotional/mental health.

A quantitative exploration of the relationships between regular yoga practice, microdosing psychedelics, wellbeing and personality variables

2021| Bettinson, S., Blatchford, E., Bright, S. J., Gringart, E.

This exploratory cross-sectional survey study (n=339) investigated differences in mood and wellbeing between samples of people who either microdose, practice yoga, or engage in neither, in light of personality trait differences in openness, neuroticism, and absorption. Microdosing and yoga practices exhibited complementary effects, as participants who practiced both had the highest absorption score, exhibited higher levels of wellbeing, and had less depression and anxiety, compared to people who either practiced yoga or microdosing, and participants recruited as controls. However, participants were recruited from different population samples, which may bias self-report, and lead to significant differences in age, gender, employment, and education between the conditions.

Effects of serotonin 2A/1A receptor stimulation on social exclusion processing

2016| Hock, A., Kraehenmann, R., Pokorny, D., Preller, K. H., Scheidegger, M., Seifritz, E., Stämpfli, P., Vollenweider, F. X.

This double-blind, randomized, counterbalanced, cross-over study (n=19) examined the effects of psilocybin (15.05mg/70kg) on the neural response to social exclusion via multimodal brain imaging. Psilocybin reduced activity in key brain regions involved in social exclusion processing, specifically the anterior midcingulate cortex (aMCC) and the middle frontal gyrus (MFG), related to decreases in the experience of social pain and reduced affective distress following social rejection. Reduced response to social exclusion also related to psilocybin changes in the experience of self.

A rapid positive influence of S-ketamine on the anxiety of patients in palliative care: a retrospective pilot study

2020| Cordes, J., Falk, E., Grau, I., Kienbaum, P., Lutterbeck, M. J., Neukirchen, M., Schlieper, D., Schwartz, J., van Caster, P.

This retrospective pilot study (n=8) investigated whether the purified enantiomer S-ketamine (17.5mg/70kg) has a positive impact during the treatment of pain for patients within palliative care, and found that it alleviated psychological distress, depression, and anxiety.

Naturalistic Use of Mescaline Is Associated with Self-Reported Psychiatric Improvements and Enduring Positive Life Changes

2021| Agin-Liebes, G. I., Davis, A. K., Lancelotta, R., Ramaekers, J. G., Uthaug, M. V.

This survey study (n=452) found that the use of mescaline led to improvements in scores on clinical conditions for those suffering from clinical conditions (anxiety 80%, depression 86%, PTSD & AUD 76%). Those who scored higher on acute mystical experience (MEQ30), ego dissolution, and psychological insight had larger improvement than those who scored lower.

A placebo-controlled study of the effects of ayahuasca, set and setting on mental health of participants in ayahuasca group retreats

2021| de Sousa Fernandes Perna, E. B., Fábregas, J. M., Kuypers, K. P. C., Mason, N. L., Ramaekers, J. G., Reckweg, J., Riba, J., Toennes, S. W., Uthaug, M. V., van Oorsouw, K.

This double-blind placebo-controlled study (n=30) controlled for expectation bias in a naturalistic ayahuasca ceremony. The use of ayahuasca led to more emotional empathy, but both groups improved as much on symptoms of depression, anxiety, and stress.

Ayahuasca: pharmacology, neuroscience and therapeutic potential

2016| Álvarez, E., de la Fuente Revenga, M., Domínguez-Clavé, E., Elices, M., Feilding, A., Friedlander, P., Pascual, J. C., Riba, J., Soler, J.

This review (2016) examines the pharmacology and neuroscience of ayahuasca, and preliminary findings which indicate the psychological mechanisms associated with its therapeutic benefits are similar to those of mindfulness-based therapy. Ayahuasca appears to enhance self-acceptance and decentering, which converges on evidence from neuroimaging studies that show activation in areas associated with emotional processing and memory formation, thereby enabling individuals to review emotional events with increased vividness and a heightened sense of “reality”. This suggests potential to treat trauma-related conditions and other disorders like borderline personality disorder.

The Heffter Research Institute: Past and Hopeful Future

2014| Nichols, D. E.

This essay describes the history and the development of the Heffter Research Institute, in their ongoing efforts to supply psilocybin for the purposes of fundamental and applied clinical research, with a prospective outlook that psilocybin will one day be recognized to have legitimate medical value and integrated within a specialized therapeutic practice.

Antidepressive and anxiolytic effects of ayahuasca: a systematic literature review of animal and human studies

2016| Crippa, J. A., Dos Santos, R. G., Hallak, J. E., Osório, F. L.

This meta-analysis (2016) examines studies on the mental health effects of ayahuasca, harmine, and harmaline within humans and animals, and shows consistent evidence for its antidepressant and anxiolytic (anxiety) effects.

Self-blinding citizen science to explore psychedelic microdosing

2021| Blemings, A., Carhart-Harris, R. L., Erritzoe, D., Feilding, A., Kartner, L., Nutt, D. J., Rosas, F. E., Szigeti, B.

This self-blinding experiment (n=191) finds that the placebo and microdosing groups both experienced similar improvements in self-rated psychological well-being and cognitive function (e.g. mood, energy, creativity) after four weeks. This study provides more evidence that microdosing benefits can be attributed to expectancy (placebo) effects.

A single inhalation of vapor from dried toad secretion containing 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT) in a naturalistic setting is related to sustained enhancement of satisfaction with life, mindfulness-related capacities, and a decrement of psychopathological symptoms

2019| Jurok, R., Kuchar, M., Kuypers, K. P. C., Lancelotta, R., Maryska, M., Mason, N. L., Páleníček, T., Rak, J., Ramaekers, J. G., Riba, J., Sulakova, A., Uthaug, M. V., van Oorsouw, K.

This open-label (naturalistic) study (n=42) with 5-MeO-DMT (smoked) found that it significantly reduced ratings of depression, anxiety, and stress. It also increased scores on mindfulness and life satisfaction. These effects correlated with higher ego dissolution and oceanic boundlessness during the acute experience.

LSD-assisted psychotherapy in patients with terminal cancer

1973| Goodman, L. E., Grof, S., Richards, W. A.

This open-label study (n=60, 1973) with LSD and DPT for end-of-life anxiety related to terminal cancer found that patients significantly improved on mood/psychological scores (29% 'dramatic', 42% 'moderate', 23% 'unchanged', 6% 'decrement'). The study also found a non-significant trend towards lower narcotic medication use.

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

2020| Davis, A. K., Grigas, P. C., Haeny, A. M., Sepeda, N. D., Sinnott, S., Williams, T. M., Xin, Y.

This survey study (n=313) suggests that psychedelic experiences (MDMA, LSD, psilocybin) could reduce symptoms of racial trauma. The participant, 30 days later, slowed moderate reductions in traumatic stress, depression, anxiety, and stress.

Effects of ayahuasca on psychometric measures of anxiety, panic-like and hopelessness in Santo Daime members

2007| Cruz, A. P. M., Dos Santos, R. G., Landeira-Fernandez, J., Motta, V., Strassman, R. J.

This double-blind placebo-controlled study (2007; n=9) investigated state and trait anxiety, hopelessness, and panic under the acute influence of ayahuasca in long-term users. Results show decreases in hopelessness and panic, but no change in anxiety.

Cancer at the dinner table: experiences of psilocybin-assisted psychotherapy for the treatment of cancer-related distress

2017| Agin-Liebes, G. I., Belser, A. B., Bossis, A. P., Devenot, N., Friedman, H. L., Guss, J., Ross, S., Swift, T. C., Terrana, S.

This interview study (n=13) analyzed the phenomenological themes associated with psilocybin therapy for anxiety and depression associated with cancer. Participants reported a felt reconnection to life, reconciliation with death, and other powerful subjective effects.

User perceptions of the benefits and harms of hallucinogenic drug use: A web-based questionnaire study

2010| Carhart-Harris, R. L., Nutt, D. J.

This survey study (n=626) investigated user perceptions of the benefits and harms of using LSD, psilocybin, MDMA, cannabis, ketamine, and alcohol. Overall, LSD and psilocybin were regarded as having the most positive impact on wellbeing, and the least harms in terms of physical and mental health.

Positive expectations predict improved mental-health outcomes linked to psychedelic microdosing

2021| Balaet, M., Buchborn, T., Carhart-Harris, R. L., Erritzoe, D., Kaertner, L. S., Kettner, H., Roseman, L., Spriggs, M. J., Steinborn, M. B., Timmermann, C.

This prospective survey study (n=81) found that expectancy effects were mostly predictive of microdosing outcomes on reductions in state anxiety, depressive symptoms (at 4-week endpoint), and positive outcomes (e.g. psychological resilience, -connectedness, -flexibility).

LSD in the supportive care of the terminally ill cancer patient

1985| Kurland, A. A.

This open-label case study (1985, n=4) describes the experience of administrating LSD (100-400μg, multiple sessions) in supportive circumstances but without much knowledge of set & setting and effective therapeutic interventions.

Replication of Ketamine’s Antidepressant Efficacy in Bipolar Depression: A Randomized Controlled Add-On Trial

2012| Brutsche, N. E., Cravchik, A., Diazgranados, N., Franco-Chaves, J., Ibrahim, L., Liberty, V., Luckenbaugh, D. A., Marquardt, C. A., Selter, J., Zarate, C. A.

This double-blind, randomized, crossover, placebo-controlled replication study (n=15) investigated the effects of ketamine (35mg) on patients with treatment-resistant bipolar depression, and found rapid improvements of depressive symptoms, suicidal ideation, and subjective well-being within 40 minutes after infusion and up to 3 days after.

The peak experience variable in DPT-assisted psychotherapy with cancer patients

2012| Dileo, F. B., Rhead, J. C., Richards, W. A., Yensen, R.

This study (1977; n = 34) found that peak experiences may be an important factor in determining the efficacy of DPT-assisted psychotherapy for cancer patients.

Antidepressant effects of a single dose of ayahuasca in patients with recurrent depression: a preliminary report

2015| Crippa, J. A., de Araujo, D. B., Dos Santos, R. G., Hallak, J. E., Macedo, L., Maia-de-Oliveira, J. P., Osório, F. L., Riba, J., Sanches, R. F., Wichert-Ana, L.

This open-label study (n=6) found that a single dose of ayahuasca has fast-acting anxiolytic and antidepressant effects (up to 21 days later, MADRS) in patients with a current depressive episode.

Attenuation and anticipation: A therapeutic use of lysergic acid diethylamide

1972| Kast, E.

This open-label clinical study (n=128) investigated whether LSD (100μg) can alleviate death-anxiety in terminally ill patients by decreasing the anticipation of their illness, and found that the administration of LSD was universally well tolerated. Specific effects included a general lift of mood that lasted for 11-12 hours, acute pain relief that lasted 12 hours, decreased the total pain intensity for 3 weeks, and diminished concern over the anticipation of death for up to 3 days after administration.

Ayahuasca in adolescence: a preliminary psychiatric assessment

2011| Alonso, J. N., da Silveira, D. X., de Rios, M. D., Doering-Silveira, E., Grob, C. S., Lopez, E., Tacla, C.

This study (n=80) evaluated the psychiatric health of adolescents who used ayahuasca in a religious context, compared to a matched control group of adolescents who did not use ayahuasca. The authors found that, compared to controls, considerable lower frequencies of positive scoring for anxiety, body dysmorphism, and attentional problems were detected among ayahuasca-using adolescents despite overall similar psychopathological profiles.

Individual Experiences in Four Cancer Patients Following Psilocybin-Assisted Psychotherapy

2018| Agin-Liebes, G. I., Belser, A. B., Bogenschutz, M. P., Bossis, A. P., Guss, J., Malone, T., Mennenga, S. E., Owens, L. T., Podrebarac, S. K., Ross, S.

This case study describes patients (n=4) from a randomized, double-blind, placebo-controlled trial investigating single-dose psilocybin (21mg/70kg) psychotherapy to treat cancer-related anxiety and depression. These four participants’ personal narratives extended beyond the cancer diagnosis itself, frequently revolving around themes of self-compassion and love, acceptance of death, and memories of past trauma.

Altered insula connectivity under MDMA

2017| Carhart-Harris, R. L., Erritzoe, D., Feilding, A., Nest, T., Nutt, D. J., Roseman, L., Walpola, I. C.

This within-subjects, double-blind, randomized, placebo-controlled study (n=25) investigated the effects of MDMA (100mg) on brain connectivity, and found that it decreased functional connectivity insula/salience network, which was also correlated with baseline trait anxiety and acute experiences of altered bodily sensations under MDMA.

Therapeutic Use of LSD in Psychiatry: A Systematic Review of Randomized-Controlled Clinical Trials

2020| Elices, M., Farré, M., Fonseca, F., Fuentes, J. J., Torrens, M.

This review (2020) presents the results of 11 randomized-controlled clinical trials (n=567) involving the therapeutic administration of LSD (20-800 μg). Multiple variables regarding LSD treatment, therapeutic approach, and quality of experience were revealed and related to therapeutic outcomes. The authors find the strongest evidence to be for the use of LSD in the treatment of alcoholism, but highlight the lack of double-blind studies.

Psilocybin-Assisted Group Therapy and Attachment: Observed Reduction in Attachment Anxiety and Influences of Attachment Insecurity on the Psilocybin Experience

2020| Anderson, B. T., Ortigo, K. M., Stauffer, C., Woolley, J. D.

This follow-up study (n=18) to Anderson and colleagues (2020) finds that attachment anxiety, but not attachment avoidance, decreased significantly 3 months after psilocybin-assisted group therapy.

MDMA-assisted psychotherapy for treatment of anxiety and other psychological distress related to life-threatening illnesses: a randomized pilot study

2020| Andries, J., Carlin, S. C., Doblin, R., Emerson, A., Feduccia, A. A., Hamilton, S., Jerome, L., Mithoefer, M. C., Sola, E., Wang, J. B., Williams, E., Wolfson, P. E., Yazar-Klosinski, B.

This double-blind, placebo-controlled study (n=18) with MDMA (125mg, 2 sessions) in combination with psychotherapy found no significant difference in anxiety in a population with life-threatening illnesses.

LSD-assisted psychotherapy for anxiety associated with a life-threatening disease: a qualitative study of acute and sustained subjective effects

2014| Kirchner, K.

This follow-up study (n=10) found long-term (12-month) positive outcomes from a single high-dose of LSD (200 μg) in combination with psychotherapy. The positive effects included reduced anxiety and a higher quality of life.

Safety and efficacy of lysergic acid diethylamide-assisted psychotherapy for anxiety associated with life-threatening diseases

2014| Brenneisen, R., Doblin, R., Gasser, P., Holstein, D., Michel, Y., Passie, T., Yazar-Klosinski, B.

This double-blind, placebo-controlled study (n=12) showed that LSD (200 μg, 2 sessions) in combination with psychotherapy was safe to use and trended towards a positive effect on end-of-life anxiety.

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

2020| Barrett, F. S., Davis, A. K., Griffiths, R. R.

This survey study (n=985) finds that psychological flexibility fully mediated the effects of mystical/peak experiences on depression/anxiety.

Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer

2010| Chopra, G. S., Danforth, A. L., Greer, G. R., Grob, C. S., Hagerty, M., Halberstadt, A. L., McKay, C. R.

This is the first (modern) double-blind placebo-controlled study (n=12) of psilocybin (14mg/70kg) for the treatment of (end-of-life) anxiety (and depression) related to cancer.

Perceived outcomes of psychedelic microdosing as self-managed therapies for mental and substance use disorders

2020| Amanda, N., Jungaberle, H., Lea, T., Schecke, H., Scherbaum, N.

This survey (n=1102) study found positive effects after microdosing psychedelics (44% reported 'much better' mental health), but was limited to self-reports.

Psychedelic Treatment for Trauma-Related Psychological and Cognitive Impairment Among US Special Operations Forces Veterans

2020| Amoroso, T., Averill, L. A., Barsuglia, J. P., Davis, A. K., Sepeda, N. D.

This survey study (n=51) found very large effects on mental health for special forces veterans after ibogaine and 5-MeO-DMT treatment.

Patient Experiences of Psilocybin-Assisted Psychotherapy: An Interpretative Phenomenological Analysis

2017| Agin-Liebes, G. I., Belser, A. B., Bossis, A. P., Devenot, N., Friedman, H. L., Guss, J., Ross, S., Swift, T. C.

This qualitative analysis of experiences may help form new hypotheses on why a psychedelic experience works. Found is that participants experienced strong emotions, partly conveyed by music.

Psilocybin produces substantial and sustained decreases in depression and anxiety in patients with life-threatening cancer: A randomized double-blind trial

2016| Griffiths, R. R., Johnson, M. W.

This study investigated the effects of a high dose of psilocybin on depression and anxiety in patients with life-threatening cancer. It found significant improvements, even without psychotherapy (as many other studies do provide).

Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: A randomized controlled trial

2016| Agin-Liebes, G. I., Babb, J., Belser, A. B., Bossis, A. P., Cohen, B., Corby, P., Guss, J., Kalliontzi, K., Malone, T., Mennenga, S. E., Ross, S., Schmidt, B. L., Su, Z.

This double-blind placebo-controlled study (n=29) for those suffering from anxiety and depression, related to cancer, improved significantly (60-80% of participants) after a single dose of psilocybin (21mg/70kg) in combination with psychotherapy.

Long-term follow-up of psilocybin-assisted psychotherapy for psychiatric and existential distress in patients with life-threatening cancer

2020| Agin-Liebes, G. I., Bossis, A. P., Fischer, S., Grigsby, J., Guss, J., Malone, T., Mennenga, S. E., Ponté, K. L., Ross, S., Yalch, M. M.

This is a follow-up study (n=16) at an average of 3.8 years after a single dose of psilocybin, in combination with psychotherapy, for patients suffering from existential distress related to cancer. Approximately 60-80% of participants still experienced reduced anxiety or depressive symptoms. This adds to the body of research that indicates that the positive of a guided psychedelic experience can be long-lasting.


This section compares the research with psychedelics to other therapies, medicines, or treatments.


This section highlights the various measures used and their use in research.


Who are the top researches in this area, the ones who have done the groundbreaking research.


What do we not know at this time? Where are the gaps in our knowledge and are we closing it?


The companies that are actively engaged in researching this topic or (planning to) provide therapy focussed on this topic.

Outside Academia

This section highlights everything done outside of academia, from popular press to books and non academic research.