EClinicalMedicine
September 24, 2020
B. Anderson, Alicia Danforth, Prof Robert Daroff et al.
271 citations
Psilocybin-assisted group therapy is feasible, relatively safe, and potentially effective for reducing demoralization in older long-term AIDS survivor (OLTAS) gay men, a population with high levels of demoralization and traumatic loss. In an open-label study, participants with moderate-to-severe demoralization received 8-10 group therapy visits and one psilocybin administration (0.3-0.36 mg/kg). The primary clinical outcome showed a reduction in demoralization from baseline to end-of-treatment and to 3-month follow-up, with a moderate effect size (partial eta-squared = 0.47, 90% CI 0.21-0.60). Groups may offer an efficient model for delivering psychotherapy alongside psilocybin to patients with complex needs.
Journal of Psychoactive Drugs
March 15, 2019
Alexander Trope, B. Anderson, Andrew R. Hooker et al.
113 citations
A systematic review of English- and Spanish-language publications identified experimental studies of psychedelic-assisted group therapy, an area overlooked by prior reviews that focused on individual psychotherapy. The review characterizes these studies by clinical approach, experimental method, and outcomes. It aims to generate hypotheses for future research on psychedelic-assisted psychotherapy, group process, and interpersonal functioning, given renewed clinical interest in psychedelic medicines.
ACS Pharmacology & Translational Science
December 9, 2020
Christopher S. Stauffer, B. Anderson, Kile Ortigo et al.
65 citations
Attachment insecurity, measured as anxiety and avoidance, is an early-life risk factor for psychopathology. Psilocybin-assisted psychotherapy may reduce attachment anxiety. In a study of 18 male long-term AIDS survivors with moderate-severe demoralization, attachment anxiety decreased significantly from baseline to three months after a single psilocybin session embedded in group therapy. Attachment avoidance did not change. Higher baseline attachment anxiety predicted stronger mystical-type experiences during the psilocybin session, while higher baseline attachment avoidance predicted more challenging experiences. These results suggest that psilocybin-assisted psychotherapy could be optimized by considering individual attachment styles.
Neuropharmacology
August 13, 2022
Ingrid Donato, Veronica Magar, Sean J. Belouin et al.
49 citations
Psychedelic and entactogen medicines like psilocybin and MDMA, when combined with psychosocial support, show potential for safe, rapid, and durable clinical improvements. Both have received Breakthrough Therapy designation from the US FDA and may gain full approval, with similar regulatory steps in other countries. Regulatory changes are also increasing access to legal or decriminalized psychedelic use outside medical settings. This review covers historical use, current evidence, and policy considerations around standards of practice, consumer protection, community engagement, equitable access, and data standards. It suggests a public-private partnership involving diverse stakeholders to co-create best practices and public policies supporting responsible, ethical use.
Journal of Humanistic Psychology
June 12, 2021
Gabrielle Agin-Liebes, Eve Ekman, B. Anderson et al.
47 citations
In a qualitative study of nine gay cisgender men diagnosed with HIV before 1996 and experiencing significant trauma symptoms, psilocybin-assisted group therapy helped participants shift from habitual, evaluative thinking to mindful, experiential awareness. During psilocybin sessions, individuals processed and released previously avoided feelings such as grief and shame, and accessed positive emotions including joy, gratitude, love, care, and compassion. The treatment also supported meaning-making and posttraumatic growth across psychological, relational, and spiritual dimensions, as participants integrated past traumas into their life narratives. These findings suggest that combining group therapy with psilocybin may enhance trauma processing by reinforcing social cohesion, safety, trust, and belonging.
Anthropology of Consciousness
March 1, 2012
B. Anderson
29 citations
Conventional psychiatry often views psychedelic-induced altered states as pathological, a perspective that shapes scientific research on ayahuasca's potential to treat depression and anxiety. Analysis of academic literature on ayahuasca's psychological effects reveals that different experimental approaches are influenced to varying degrees by this pathological framing, yet findings still indicate some therapeutic utility of the ayahuasca-induced modified state of consciousness. The article suggests that psychiatry's dominant reasoning about psychedelic states should be reconsidered to better assess their clinical potential.
Neuropharmacology
May 13, 2022
Cynthia E. Ortiz, Haley Maria Dourron, Noah W Sweat et al.
26 citations
Psilocybin-facilitated psychotherapy may be effective across many mental health conditions, but vulnerable populations, who carry a disproportionate mental health burden, have been largely excluded from clinical research. This report highlights the need to include these groups in studies, considering their problematic historical context and differential experiences with psychedelics. It offers actionable recommendations for future research, such as improved recruitment strategies, careful communication of subjective effects, building therapeutic alliance, multicultural competence, and flexible study designs. The authors call for expanded and improved research in this rapidly advancing field.
Journal of Psychopharmacology
January 1, 2024
Lisa Bouchet, Zachary Sager, Antoine Yrondi et al.
22 citations
Older adults (65+) account for less than 1.4% of participants in psychedelic clinical trials, despite these compounds showing potential for conditions common in this age group, such as depression, anxiety, and existential distress. A systematic review of 36 trials involving 1,400 patients found only 19 were aged 65 or older. Safety data for 10 of these older adults showed no serious adverse events; only transient mild-to-moderate effects like anxiety, gastrointestinal upset, and hypertension occurred during dosing sessions. The authors conclude that psychedelic-assisted psychotherapy appears safe and well tolerated in older adults and warrants more rigorous investigation for psychiatric treatment in this population.
November 22, 2013
Beatriz Caiuby Labate, Rafael G. Dos Santos, Rick J. Strassman et al.
13 citations
Ayahuasca shows promise in treating substance abuse, with a study involving 100 participants revealing that 60% reported significant reductions in substance use after treatment. This hallucinogen, often studied within the realms of clinical psychology and sociology, highlights its potential therapeutic benefits. Participants also noted improvements in mental health, with 75% experiencing enhanced emotional well-being. The findings underscore the importance of integrating psychedelics into psychiatric practices, offering new avenues for addressing addiction and enhancing overall psychological health across diverse geographical contexts.
Scientific Reports
August 2, 2024
Jennifer Mitchell, Nicky J. Mehtani, Mallory O. Johnson et al.
9 citations
HIV-related shame predicts substance use and poor antiretroviral adherence among people with HIV, hindering national epidemic-ending goals. In a pilot clinical trial with 12 participants, psilocybin-assisted group therapy produced a large decrease in HIV-related shame, with a median reduction of 5.5 points on the HIV and Abuse Related Shame Inventory from baseline to 3-month follow-up. However, two participants experienced a paradoxical worsening of sexual abuse-related shame after psilocybin, raising concerns about its use in patients with trauma. These preliminary results suggest potential for addressing HIV-related shame but highlight cautions.
Journal of the American College of Emergency Physicians Open
August 30, 2025
Juan Carlos C. Montoy, Ralph C. Wang, Allison R. Coker et al.
3 citations
Between 2013 and 2022, calls to poison control centers involving psilocybin tripled, with nearly all of the increase occurring after 2019. This pattern was not seen for other substances. While the total number of such calls remains low, the trend may continue as psilocybin use rises.
Journal of Psychoactive Drugs
August 4, 2025
Meredith C. Meacham, Maha N. Mian, Ralph C. Wang et al.
2 citations
Among U.S. adults who have ever used a hallucinogen, four distinct patterns of lifetime use emerge: a group primarily using psilocybin (16%), a larger group using both LSD and psilocybin (46%), a group mainly using ecstasy (23%), and a group using multiple hallucinogens (15%). Older age is associated with higher odds of being in the LSD/psilocybin class compared with the psilocybin-only class, and non-White participants have higher odds of being in the ecstasy class. These overlapping use patterns suggest that clinical trials and future policies should account for polysubstance hallucinogen experiences.
European Psychiatry
April 1, 2024
N. Kabir, B. Anderson, Lisa Bouchet et al.
1 citation
Older adults are severely underrepresented in clinical trials of psychedelic-assisted therapies. A systematic review of 36 studies with 1,400 patients found that only 19 participants were aged 65 or older, less than 1.4% of the total. Detailed safety data for 10 of these older adults showed no serious adverse events; only mild-to-moderate side effects such as anxiety, gastrointestinal upset, and hypertension occurred during dosing sessions. The evidence, though limited, suggests that psychedelic-assisted psychotherapy is safe and well tolerated in older adults and should be more rigorously studied for treating psychiatric conditions in this population.
Journal of Psychoactive Drugs
January 27, 2022
Ciarán Martin Fitzpatrick, B. Anderson, Gabrielle Agin-Liebes et al.
1 citation
A case report described a person with obsessive-compulsive disorder whose symptoms lessened after consuming psilocybin-containing mushrooms. The report prompted a letter arguing that psychedelic research has moved beyond case studies and that journals should prioritize publishing clinical trials over case reports.
May 1, 2025
Jessi Humphreys, Lou Lukas, Yvan Beaussant et al.
Psilocybin, a psychoactive compound from over 200 mushroom species, has a long history in Indigenous sacred rituals. It binds to serotonin receptors, activating the serotonergic system to promote neuroplasticity, which helps individuals derive meaning from psychedelic experiences. Evidence suggests benefits for major depressive disorder, anxiety disorders, existential suffering, and substance use disorders. Dosing ranges from low psycholytic to high psychoactive levels. While physiological harm to humans appears low, further research is needed on cardiac and neurological safety in diverse and vulnerable groups. Legal access is expanding through decriminalization, legalization, and right-to-try approaches, varying by region.