Abstract
Rationale
A broad reassessment of the potential benefits of psychedelic drugs has led to the initiation of multiple major clinical trials in an effort to advance their status to become FDA-approved medications, as well as local legislative efforts to legalize or decriminalize their use.
Objectives
To use recently published data to assess potential risks and benefits of psychedelic drugs as therapeutics, as well as to synthesize what is currently known in order to generate fruitful future research directions.
Methods
A review of studies conducted since 1991 identified 14 clinical trials of classical psychedelics, including 11 of psilocybin (N = 257 participants), 1 of lysergic acid diethylamide (N = 12 participants), and 2 of ayahuasca (N = 46 participants). Other published studies (e.g., of healthy volunteers, survey studies, case reports, neuroimaging) were also considered for review.
Results
Published studies since 1991 largely support the hypothesis that small numbers of treatments with psychedelic-assisted psychotherapy can offer significant and sustained alleviation to symptoms of multiple psychiatric conditions. No serious adverse events attributed to psychedelic therapy have been reported. Existing studies have several limitations, including small sample sizes, inherent difficulty in blinding, relatively limited follow-up, and highly screened treatment populations.
Conclusions
Substantial data have been gathered in the past 30 years suggesting that psychedelics are a potent treatment for a variety of common psychiatric conditions, though the ideal means of employing these substances to minimize adverse events and maximize therapeutic effects remains controversial. Unique factors related to study design are vital for clinical researchers in the field to address.
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Abbreviations
- LSD:
-
Lysergic acid diethylamide
- MDMA:
-
3,4-Methylenedioxymethamphetamine
- PTSD:
-
Post-traumatic stress disorder
- HPPD:
-
Hallucinogen persisting perception disorder
- MDD:
-
Major depressive disorder
- MEQ:
-
Mystical Experience Questionnaire
- BPD:
-
Borderline personality disorder
- QIDS:
-
Quick Inventory of Depression Symptoms
- BDI:
-
Beck Depression Inventory
- HADS:
-
Hospital Anxiety and Depression Scale
- STAI:
-
State-Trait Anxiety Inventory
- GAD:
-
Generalized anxiety disorder
- GRID-HAM-D:
-
GRID Hamilton Depression Scale
- HAM-A:
-
Hamilton Anxiety Scale
- DMN:
-
Default mode network
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DB: no conflicts. DH: Dr. Hellerstein has received research funding support from Compass Pathways for psilocybin studies and from Pfizer, Lilly, Takeda, GeneSight, Marinus, Relmada, and IntraCellular Therapies for other studies. He is on the scientific advisory board for Reset Pharmaceuticals.
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Bender, D., Hellerstein, D.J. Assessing the risk–benefit profile of classical psychedelics: a clinical review of second-wave psychedelic research. Psychopharmacology 239, 1907–1932 (2022). https://doi.org/10.1007/s00213-021-06049-6
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DOI: https://doi.org/10.1007/s00213-021-06049-6