Trial PaperAnxiety DisordersObsessive-Compulsive Disorder (OCD)Psilocybin

Safety, Tolerability, and Efficacy of Psilocybin in 9 Patients With Obsessive-Compulsive Disorder

This double-blind, placebo-controlled study (n=9) of psilocybin (up to 21mg/70kg) found no adverse effects and improvements in OCD symptoms. Immediate improvements on the Yale-Brown Obsessive Compulsive Scale (YBOCS) varied between 23-100% reductions. Positive results were also observed after the 24 hours reported in the study.

Authors

  • Moreno, F. A.
  • Wiegand, C. B.
  • Taitano, E. K.

Published

Journal of Clinical Psychiatry
individual Study

Abstract

Anecdotal reports suggest that psychedelic agents may relieve symptoms of obsessive-compulsive disorder (OCD). This modified double-blind study investigated the safety, tolerability, and clinical effects of psilocybin, a potent 5-HT(1A) and 5-HT(2A/2C) agonist, in patients with OCD. Nine subjects with DSM-IV-defined OCD and no other current major psychiatric disorder participated in up to 4 single-dose exposures to psilocybin in doses ranging from sub-hallucinogenic to frankly hallucinogenic. Low (100 microg/kg), medium (200 microg/kg), and high (300 microg/kg) doses were assigned in that order, and a very low dose (25 microg/kg) was inserted randomly and in a double-blind fashion at any time after the first dose. Testing days were separated by at least 1 week. Each session was conducted over an 8-hour period in a controlled environment in an outpatient clinic; subjects were then transferred to a psychiatric inpatient unit for overnight observation. The Yale-Brown Obsessive Compulsive Scale (YBOCS) and a visual analog scale measuring overall obsessive-compulsive symptom severity were administered at 0, 4, 8, and 24 hours post-ingestion. The Hallucinogen Rating Scale was administered at 8 hours, and vital signs were recorded at 0, 1, 4, 8, and 24 hours after ingestion. The study was conducted from November 2001 to November 2004. Nine subjects were administered a total of 29 psilocybin doses. One subject experienced transient hypertension without relation to anxiety or somatic symptoms, but no other significant adverse effects were observed. Marked decreases in OCD symptoms of variable degrees were observed in all subjects during 1 or more of the testing sessions (23%-100% decrease in YBOCS score). Repeated-measures analysis of variance for all YBOCS values revealed a significant main effect of time on Wilks lambda (F = 9.86, df = 3,3; p = .046), but no significant effect of dose (F = 2.25, df = 3,3; p = .261) or interaction of time and dose (F = 0.923, df = 9,45; p = .515). Improvement generally lasted past the 24-hour timepoint. In a controlled clinical environment, psilocybin was safely used in subjects with OCD and was associated with acute reductions in core OCD symptoms in several subjects.

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Research Summary of 'Safety, Tolerability, and Efficacy of Psilocybin in 9 Patients With Obsessive-Compulsive Disorder'

Introduction

OCD affects roughly 2% to 3% of the population and carries a high burden of disability; many patients remain symptomatic despite standard treatments. Potent serotonin reuptake inhibitors (SRIs) and cognitive behavioural therapy are effective for some patients but typically produce only partial improvement, with an estimated 40% to 60% of adequately treated patients failing to respond fully. Anecdotal case reports and historical observations have suggested that indole-based hallucinogens such as psilocybin and LSD can produce acute reductions in obsessive and compulsive symptoms, and pharmacologically these compounds are notable agonists at 5-HT1A, 5-HT2A, and 5-HT2C receptors — sites implicated in serotonergic treatments for OCD. Moreno and colleagues designed a small proof-of-concept study to evaluate the safety, tolerability, and potential therapeutic effects of psilocybin in symptomatic, treatment-resistant OCD patients. The study also aimed to explore whether the intensity of the psychedelic experience related to changes in obsessive-compulsive symptom severity during testing. This investigation was positioned as a Phase I, exploratory evaluation to inform whether further controlled trials would be warranted.

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Study Details

Related Clinical Trial

CompletedPhase I

Safety, Tolerability, and Efficacy of Psilocybin in Patients With Obsessive-Compulsive Disorder: A Phase I Modified Dose-Escalation Study

Phase I modified dose-escalation pilot (Department of Psychiatry, University of Arizona Health Sciences Center, Tucson; collaborator: University of Texas Health Sciences Center, San Antonio) of oral psilocybin in 9 adults (7 male, 2 female, ages 26–62, mean 40.9 ± 13.2) with DSM-IV obsessive-compulsive disorder and at least one prior adequate serotonin reuptake inhibitor (SRI) trial failure (mean 3.4 ± 1.9 treatment failures; baseline Y-BOCS 18–36, mean 24.1 ± 5.9). Up to four single-dose exposures per subject were administered at least one week apart under medical supervision in an outpatient psychopharmacology research clinic with subsequent overnight observation on an affiliated psychiatric inpatient unit. Dose levels: very low (VLD) 25 µg/kg, low (LD) 100 µg/kg, medium (MD) 200 µg/kg, and high (HD) 300 µg/kg. LD, MD, and HD were assigned in fixed ascending order (open-label); the VLD was inserted randomly and in double-blind fashion at any time after the first dose. Subjects wore eyeshades, listened to a standardised music programme, and were accompanied by trained sitters during each 8-hour session. Primary outcomes: Yale-Brown Obsessive Compulsive Scale (Y-BOCS) and a visual analog scale (VAS) for overall OC symptom severity at 0, 4, 8, and 24 hours post-ingestion; Hallucinogen Rating Scale (HRS) at 8 hours; vital signs at 0, 1, 4, 8, and 24 hours. Twenty-nine total psilocybin doses were administered (all 9 received LD; 7 received VLD and MD; 6 received all four). Approved by the University of Arizona Human Subjects Committee and the U.S. Food and Drug Administration (FDA) under an Investigational New Drug application. Funded by the Multidisciplinary Association for Psychedelic Studies (MAPS), the Heffter Research Institute (with support from Peggy Hitchcock), and the Nathan Cummings Foundation. No public registry ID exists: the trial pre-dates the 2005 ICMJE registration mandate and the 2007 FDAAA requirement, and the paper reports no NCT/IND/protocol number.

Started
Type
interventional
Randomized
No
Registry ID
MORENO-2006-JCP-PSILOCYBIN-OCD

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Deane, G. · Philosophy and the Mind Sciences (2020)

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Psychedelics and Psychedelic-Assisted Psychotherapy

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Learning to Let Go: A Cognitive-Behavioral Model of How Psychedelic Therapy Promotes Acceptance

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

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

Sartori, S. B., Singewald, N. · Pharmacology and Therapeutics (2019)

Toward a contextual psychedelic-assisted therapy: Perspectives from Acceptance and Commitment Therapy and contextual behavioral science

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REBUS and the Anarchic Brain: Toward a Unified Model of the Brain Action of Psychedelics

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Replication and extension of a model predicting response to psilocybin

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41 cited
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Nutt, D. J. · Dialogues in Clinical Neuroscience (2019)

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States and traits related to the quality and consequences of psychedelic experiences

Russ, S. L., Carhart-Harris, R. L., Maruyama, G. et al. · Psychology of Consciousness Theory Research and Practice (2019)

Trait Openness and serotonin 2A receptors in healthy volunteers: A positron emission tomography study

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Current perspectives on psychedelic therapy: use of serotonergic hallucinogens in clinical interventions

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Increased amygdala responses to emotional faces after psilocybin for treatment-resistant depression

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Does getting high hurt? Characterization of cases of LSD and psilocybin-containing mushroom exposures to national poison centers between 2000 and 2016

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53 cited
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191 cited
DARK Classics in Chemical Neuroscience: Psilocybin

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

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Neuroendocrine Associations Underlying the Persistent Therapeutic Effects of Classic Serotonergic Psychedelics

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Increased nature relatedness and decreased authoritarian political views after psilocybin for treatment-resistant depression

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Connectome-harmonic decomposition of human brain activity reveals dynamical repertoire re-organization under LSD

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Psilocybin with psychological support for treatment-resistant depression: six-month follow-up

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Psilocybin with psychological support improves emotional face recognition in treatment-resistant depression

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88 cited
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Patients’ accounts of increased “Connectedness” and “Acceptance” after psilocybin for treatment-resistant depression

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

Thomas, K., Malcolm, B., Lastra, D. · Journal of Psychoactive Drugs (2017)

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164 cited
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Kaelen, M. · Imperial College London (2017)

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Hallucinogens and Serotonin 5-HT2A Receptor-Mediated Signaling Pathways

López-Giménez, J. F., González-Maeso, J. · Current Topics in Behavioral Neurosciences (2017)

211 cited
The Effects of Hallucinogens on Gene Expression

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

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Psychedelics in the treatment of unipolar mood disorders: a systematic review

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Psilocybin for treating substance use disorders?

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Clinical Applications of Hallucinogens: A Review

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174 cited
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Psychedelics

Nichols, D. E. · Pharmacological Reviews (2016)

Antidepressive, anxiolytic, and antiaddictive effects of ayahuasca, psilocybin and lysergic acid diethylamide (LSD): a systematic review of clinical trials published in the last 25 years

Dos Santos, R. G., Osório, F. L., Crippa, J. A. et al. · Therapeutic Advances in Psychopharmacology (2016)

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

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130 cited
The paradoxical psychological effects of lysergic acid diethylamide (LSD)

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253 cited
New World Tryptamine Hallucinogens and the Neuroscience of Ayahuasca

McKenna, D., Riba, J. · Current Topics in Behavioral Neurosciences (2016)

Serotonergic Hallucinogen-Induced Visual Perceptual Alterations

Kometer, M., Vollenweider, F. X. · Behavioral Neurobiology of Psychedelic Drugs (2016)

Indoleamine Hallucinogens in Cluster Headache: Results of the Clusterbusters Medication Use Survey

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91 cited
Underground MDMA-, LSD-and 2-CB-assisted individual and group psychotherapy in Zurich: Outcomes, implications and commentary

Sessa, B., Fischer, F. M. · Drug Science Policy and Law (2015)

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

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A qualitative report on the subjective experience of intravenous psilocybin administered in an FMRI environment

Nutt, D. J., Carhart-Harris, R. L. · Current Drug Abuse Reviews (2015)

50 cited
Acute Effects of the Novel Psychoactive Drug 2C-B on Emotions

González, D., Torrens, M., Farré, M. · BioMed Research International (2015)

56 cited
Psilocybin and obsessive compulsive disorder

Wilcox, C. E. · Journal of Psychoactive Drugs (2014)

Classical hallucinogens as antidepressants? A review of pharmacodynamics and putative clinical roles

Tracy, D., Baumeister, D., Barnes, G. et al. · Therapeutic Advances in Psychopharmacology (2014)

The entropic brain: a theory of conscious states informed by neuroimaging research with psychedelic drugs

Carhart-Harris, R. L., Leech, R., Shanahan, M. et al. · Frontiers in Human Neuroscience (2014)

Psilocybin - Summary of knowledge and new perspectives

Tylš, F., Páleníček, T., Horacek, J. · European Neuropsychopharmacology (2013)

Broadband Cortical Desynchronization Underlies the Human Psychedelic State

Muthukumaraswamy, S. D., Carhart-Harris, R. L., Moran, R. J. et al. · Journal of Neuroscience (2013)

427 cited
Effects of Schedule I drug laws on neuroscience research and treatment innovation

King, C., Nichols, D. E. · Nature Reviews Neuroscience (2013)

Multiple receptors contribute to the behavioral effects of indoleamine hallucinogens

Halberstadt, A. L., Geyer, M. A. · Neuropharmacology (2011)

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

Grob, C. S., Danforth, A. L., Chopra, G. S. et al. · JAMA Psychiatry (2011)

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

Studerus, E., Kometer, M., Hasler, F. et al. · Journal of Psychopharmacology (2010)

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

Carhart-Harris, R. L., Nutt, D. J. · Journal of Substance Use (2010)

Serotonin and serotonin receptors in hallucinogen action

Halberstadt, A. L., Nicholas, C. R. · Handbook of Behavioral Neuroscience (2010)

Human hallucinogen research: guidelines for safety

Johnson, M. W., Richards, W. A., Griffiths, R. R. · Journal of Psychopharmacology (2008)

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