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Alan K. Davis

Multidisciplinary Association for Psychedelic Studies, The Ohio State University

57 papers in the library · 4,266 citations · publishing 2015-2026

Papers

Race, Ethnic, and Sex Differences in Prevalence of and Trends in Hallucinogen Consumption Among Lifetime Users in the United States Between 2015 and 2019

Frontiers in Epidemiology March 23, 2022 Alan K. Davis, Brooke J. Arterberry, Yitong Xin et al. 20 citations

Asian females had the highest prevalence of past-year hallucinogen use (35.06%), two or more times that of White males and females and Native American males. More than half of White males and females, Multiracial males, and Hispanic males had ever used psilocybin or LSD, while less than a quarter of Black males and females reported lifetime psilocybin use. Native American males had the lowest lifetime MDMA use (17.62–33.30%) but the highest lifetime peyote use (40.37–53.24%). Pacific Islander males had the highest lifetime mescaline use (28.27%), and Pacific Islander males and females had the highest lifetime DMT use (15.68–38.58%).

Preliminary safety and effectiveness of psilocybin-assisted therapy in adults with fibromyalgia: an open-label pilot clinical trial

Frontiers in Pain Research March 18, 2025 Jenna McAfee, Avinash Hosanagar, Vijay Tarnal et al. 18 citations

In a small open-label pilot trial, five people with fibromyalgia received two doses of psilocybin (15 mg and 25 mg) along with psychotherapy. The treatment was well-tolerated: there were temporary increases in blood pressure or heart rate during dosing that returned to normal, no serious adverse events, and four of five participants had short-lived headaches. One month after the second dose, participants reported large reductions in pain severity, pain interference, and sleep disturbance. One participant rated their symptoms as very much improved, two as much improved, and two as minimally improved. Recruitment stopped early due to generalizability concerns and changing FDA guidance, but the results suggest psilocybin-assisted therapy is safe for fibromyalgia and warrants larger trials.

Psychedelic treatment for co-occurring alcohol misuse and post-traumatic stress symptoms among United States Special Operations Forces Veterans

Journal of Psychedelic Studies November 19, 2021 Pratheek Mangini, Lynnette A. Averill, Alan K. Davis 18 citations

Among 27 Special Operations Forces Veterans who reported risky drinking before a psychedelic clinical program in Mexico, retrospective reports showed very large reductions in alcohol use and post-traumatic stress symptoms from before to after treatment, with 85% reducing drinking to non-risky levels (33% abstinent, 52% non-risky drinking). Psychological flexibility increased substantially and was strongly associated with both reductions. The authors call for rigorous longitudinal studies to determine whether psychedelic-assisted therapy holds promise for this population.

Psilocybin for the Treatment of Depression: A Promising New Pharmacotherapy Approach.

Current topics in behavioral neurosciences January 1, 2022 Gabrielle Agin-Liebes, Alan K. Davis 16 citations

Depression is the leading cause of global disability and a major contributor to the global burden of disease. Early experimental trials suggest that psilocybin, a serotonergic psychedelic, combined with therapeutic support shows promise for treating depression, with large effect sizes. Neuroimaging reveals dynamic effects of psilocybin on brain functional activity. This chapter reviews methods and findings from three small clinical trials examining psilocybin therapy for major depressive disorder and treatment-resistant depression, presenting insights from functional magnetic resonance imaging and qualitative analyses, along with study limitations and future directions.

Application of the Passionate Attachment Model to Recreational Use of MDMA/Ecstasy

Journal of Psychoactive Drugs January 1, 2015 Alan K. Davis, Harold Rosenberg 15 citations

People who persistently use ecstasy without being addicted may have a passionate attachment to the activity. In a community sample of ecstasy users, both obsessive and harmonious passion scores were linked to lower self-efficacy to refuse the drug and greater use of ecstasy to cope with worries. Obsessive passion was partially associated with more frequent use, more lifetime uses, and more pills consumed per occasion, whereas harmonious passion was not tied to those consumption measures. The modified Passion Scale could supplement assessments of the psychology behind ecstasy use.

Predictors of attitudes toward psychedelics among psychologists in the USA

Drugs Education Prevention and Policy September 4, 2022 Jason B. Luoma, Brian Pilecki, Alan K. Davis et al. 13 citations

Psychologists' attitudes toward psychedelics vary with individual characteristics. Men, younger psychologists, those living in the West or Northeast US, those with greater knowledge of risks and benefits, those who are religiously unaffiliated, and those with direct or indirect experience with psychedelics report more positive attitudes. Previous addiction treatment training was not associated with more positive attitudes. These findings can help inform efforts to improve attitudes, such as using case studies in public education.

Differences in attitudes and beliefs about psychedelic-assisted therapy among social workers, psychiatrists, and psychologists in the United States

Journal of Psychedelic Studies August 21, 2023 Stacey B. Armstrong, Adam W. Levin, Yitong Xin et al. 12 citations

Among 856 U.S. mental health professionals—social workers, psychiatrists, and psychologists—there were no differences in confidence that psychedelic-assisted therapy (PAT) would be effective. However, psychiatrists showed a better understanding of PAT than social workers. Psychologists rated PAT as more acceptable than social workers did, and psychologists also rated it as a more reasonable treatment approach than both social workers and psychiatrists. Social workers perceived greater disadvantages of PAT than psychologists and psychiatrists, and they were less likely than both other groups to believe PAT could permanently improve clients' lives. The findings indicate a need for education and training across professions as PAT moves toward approval.

Ketamine-assisted psychotherapy for trauma-exposed patients in an outpatient setting: A clinical chart review study

Journal of Psychedelic Studies October 1, 2021 Alan K. Davis, Pratheek Mangini, Yitong Xin 10 citations

Trauma exposure across the lifespan increases risks for PTSD, depression, anxiety, and disability. In a retrospective chart review of 18 patients (average age 45) who completed six sessions of sublingual ketamine-assisted body-centered psychotherapy in an outpatient clinic, improvements in depression were statistically significant and meaningful, with a medium effect size. Improvements in PTSD symptoms and global disability were meaningful but not statistically significant. No improvements in anxiety were observed. The study was underpowered and unrepresentative, requiring replication with larger, more diverse samples.

A Field-Wide Review and Analysis of Study Materials Used in Psilocybin Trials: Assessment of Two Decades of Research

Psychedelic Medicine January 20, 2025 Marianna Graziosi, Gabrielle Agin-Liebes, Mary P Cosimano et al. 9 citations

Psilocybin and other serotonergic psychedelics are used in research settings with safety measures including controlled environments, staff presence, screening, and psychoeducation. An analysis of study materials from psilocybin trials over the past two decades found that psychoeducation documents varied but commonly emphasized biological and physical safety, psychological safety and well-being, aspects of setting, and the potential for expectancies. The materials prioritized biological and psychological safety across all sites. The authors also identified elements unrelated to safety that may contribute to participant expectancies and suggest these extrapharmacological factors be studied systematically to maximize safety while minimizing extraneous expectancies.

Effect of psilocybin therapy on suicidal ideation, attempts, and deaths in people with psychiatric diagnoses: a systematic review and meta-analysis

Therapeutic Advances in Psychopharmacology September 1, 2025 Stanley Wong, Gray Meckling, Nicholas Fabiano et al. 6 citations

A systematic review and meta-analysis of nine randomized controlled trials involving 593 adults with psychiatric diagnoses found that psilocybin therapy led to a small but significant decrease in suicidal ideation compared to control conditions. No studies reported suicide attempts or deaths. The analysis showed low heterogeneity and no publication bias, though two studies had a high risk of bias. Current evidence is limited by small sample sizes, insufficient follow-up data, and inadequate assessment of blinding.

Naturalistic psychedelic experiences and gender-based self-acceptance in transgender and gender-expansive people

International Journal of Transgender Health March 19, 2025 Skylar J. Gaughan, Angie R. Wootton, Daphne Krantz et al. 6 citations

Transgender and gender-expansive (TGE) people use psychedelics in naturalistic, non-clinical settings to explore and affirm their gender identity. Interviews with 20 TGE individuals revealed three main themes: the mindset and physical setting of a psychedelic experience shape its quality; such experiences often increase self-acceptance of gender identity through greater self-compassion and a broader concept of gender; and participants reported both challenging effects like gender dysphoria and benefits like gender euphoria. The findings suggest clinicians should help TGE clients prepare a gender-affirming setting before psychedelic use and support shifts in gender understanding afterward.

Psychedelic research at a crossroads

Science September 19, 2024 Stacey B. Armstrong, Alan K. Davis 6 citations

Psychedelic-assisted therapy (PAT) combines hallucinogenic drugs like psilocybin and MDMA with psychotherapy, showing potential for treating mental health conditions that affect one in eight people worldwide. Clinical trials in the US and Europe suggest PAT may offer shorter treatment times and stronger effects than existing therapies. However, the field faces significant controversy due to unanswered questions about safety and effectiveness, highlighted by the FDA's recent decision against approving MDMA therapy for PTSD and the retraction of several MDMA trial papers due to unethical therapist conduct and data integrity issues. The research community must address these obstacles to transition from exploratory trials to established, evidence-based treatments.

Psilocybin use patterns and perception of risk among a cohort of Black individuals with Opioid Use Disorder

Journal of Psychedelic Studies August 5, 2022 John Clifton, Annabelle M. Belcher, Aaron D. Greenblatt et al. 6 citations

Among Black individuals diagnosed with Opioid Use Disorder recruited from an urban methadone program, most had heard of psilocybin mushrooms but only 17.8% had ever used them. Over 80% perceived a risk or were unsure of the risk for most psilocybin-related items. About half were willing to try therapy incorporating psilocybin, and half said they would be more likely to try it if FDA-approved for OUD. Most preferred to stay on methadone alone; only one participant chose psilocybin treatment without methadone. The authors suggest culturally informed treatment models and outreach to increase minority representation in psilocybin research.

Increases in Aesthetic Experience Following Ayahuasca Use: A Prospective, Naturalistic Study

Journal of Humanistic Psychology February 27, 2024 Jacob S. Aday, Emily K. Bloesch, Alan K. Davis et al. 5 citations

People who attended an ayahuasca retreat showed increased appreciation of art and beauty one week and one month later, according to a survey of 54 participants. Contrary to expectations, intense drug effects such as mystical experiences, awe, or ego dissolution did not predict these changes. The open-label design limits certainty, but the findings align with anecdotal reports of lasting shifts in aesthetic attitudes after psychedelic use. Further research is needed to identify the mechanisms behind these changes.

Five-year outcomes of psilocybin-assisted therapy for Major Depressive Disorder

Journal of Psychedelic Studies September 4, 2025 Alan K. Davis, Meghan DellaCrosse, Nathan D. Sepeda et al. 4 citations

Over a five-year follow-up period, psilocybin-assisted therapy produced significant and sustained reductions in depression for people with major depressive disorder. Among the 18 participants who completed the study, 67% remained in remission for at least five years after treatment. Anxiety and functional impairment also improved. Qualitative interviews revealed lasting positive changes in mindset, emotional health, and relationships, including enhanced empathy, self-acceptance, and improved interpersonal relationships. No severe adverse events were reported. These findings support the long-term efficacy and safety of psilocybin-assisted therapy for reducing depressive symptoms and improving mental health.

The Epidemiology of Psychedelic Use Among United States Military Veterans

Journal of Psychoactive Drugs September 12, 2024 Katinka Hooyer, Rachel Yehuda, Alan K. Davis et al. 4 citations

About half of U.S. military veterans surveyed reported using psychedelics, most often for healing or treatment (70%) and spiritual purposes (48%). The vast majority (85%) said they benefited from use. Veterans who used psychedelics indicated they would be more likely to use VA services, and they expressed greater interest in psychedelic therapy compared to non-users. However, some adverse outcomes were reported, suggesting that without proper preparation and support, psychedelics may carry risks. The findings point to a potential role for psychedelic-assisted approaches in veteran mental health care.

Seeing the forest for the trees: An ecological systems theory approach to addressing emergent issues in psychedelic-assisted therapy research

Journal of Psychedelic Studies June 5, 2024 Meghan DellaCrosse, A. Garcia-Romeu, Alan K. Davis 4 citations

A lack of consensus and theoretical clarity in psychedelic-assisted therapy research has led to polarized debates and unusual regulatory recommendations, such as removing psychological and medical safety measures to better study drug effects. This commentary argues that an ecological systems theory approach, adapted from Bronfenbrenner, can make contextual and practical factors explicit and testable in research. The proposed conceptual model aims to improve measurement of acute subjective experience and address limitations in current approaches. The authors suggest this framework could help reconcile conflicting perspectives and enhance safety in ongoing clinical trials.

Translation and Initial Psychometric Evaluation of Spanish Versions of Three Psychedelic Acute Effects Measures: Mystical, Challenging, and Insight Experiences

Journal of Psychoactive Drugs July 14, 2023 Christopher Timmermann, Aki Nikolaidis, Alan K. Davis et al. 4 citations

Spanish translations of three questionnaires measuring acute psychedelic effects—the Psychological Insight Questionnaire (PIQ), Challenging Experiences Questionnaire (CEQ), and Mystical Experiences Questionnaire (MEQ)—showed good psychometric properties in a sample of 442 native Spanish speakers. Confirmatory factor analysis confirmed that the factor structures matched the original English versions, and this consistency held across subgroups who had used LSD or psilocybin. Construct validity was supported by positive associations between the PIQ and MEQ and between these measures and changes in cognitive fusion, alongside negative associations with changes in prosocial behaviors. Predictive validity was indicated by strong relationships between persisting effects and scores on the MEQ and PIQ. The Spanish versions can be reliably used in research with Spanish-speaking populations.

Increases in aesthetic experience following ayahuasca use: An open-label, naturalistic study

May 15, 2023 Jacob S. Aday, Emily K. Bloesch, Alan K. Davis et al. 3 citations preprint

People who attended an ayahuasca retreat showed increased engagement with aesthetic experiences—such as appreciation of art, nature, and beauty—one week and one month afterward, compared to before the retreat. The study followed 54 participants and measured aesthetic experience using a validated questionnaire. Although participants reported strong mystical-type experiences, awe, and ego dissolution during their ayahuasca sessions, none of these acute effects predicted the long-term increase in aesthetic engagement. The open-label design limits certainty, but the findings support anecdotal reports that psychedelics can enhance aesthetic appreciation and point to a new area for future research.

Psychedemia: Charting the future of interdisciplinary Psychedelic Studies

Journal of Psychedelic Studies December 29, 2023 Neşe Devenot, Brian A. Pace, Jason Slot et al. 1 citation

The field of psychedelic scholarship is expanding rapidly across clinical research, neuroscience, pharmacology, and the humanities. This special issue introduces the Psychedemia 2022 conference, hosted by the Center for Psychedelic Drug Research and Education at The Ohio State University, which brought together diverse academic disciplines to discuss integrating psychedelics into society. The conference built on the first Psychedemia in 2012 at the University of Pennsylvania, which helped establish Psychedelic Studies as an interdisciplinary field. As psychedelic research gains mainstream acceptance and a projected multi-billion-dollar medical market emerges, academics have a crucial role in articulating stakeholder concerns and shaping policy, theory, and methodology across social, legal, economic, and environmental dimensions.

Effects of ayahuasca on gratitude and relationships with nature: An open-label, naturalistic study

June 7, 2023 Jacob S. Aday, Emily K. Bloesch, Alan K. Davis et al. 1 citation preprint

People who attended an ayahuasca retreat showed increased gratitude, nature relatedness, and nature appreciation one week and one month afterward, compared with before the retreat. Mystical-type experiences and feelings of awe during the retreat were weakly to moderately linked to these increases, while ego dissolution was not. The findings suggest that the mystical and awe-inducing aspects of ayahuasca may lead to personality changes that benefit mental health and prosocial attitudes, though more research is needed to confirm the results.

Baseline Resilience as a Predictor of Ayahuasca Acute Effects and Moderator of the Relationship between Acute Effects and Psychospiritual Outcomes

Psychedelic Medicine May 9, 2026 Yitong Xin, Alan K. Davis, Susan Yoon et al.

People with higher psychological resilience before an ayahuasca retreat reported more intense acute challenging experiences, such as nausea or emotional distress. Resilience also moderated how those challenging experiences related to later meaning-making: among participants with higher baseline resilience, the link between acute difficulty and a subsequent search for meaning in life was stronger. The findings suggest that resilience may help individuals transform difficult psychedelic moments into psychospiritual growth, pointing to the value of incorporating resilience-building into retreat preparation and integration programs.

Transgender and gender-expansive psychedelic users’ concerns about colonization, racism, and medicalization in western psychedelic science

Psychedelics March 7, 2026 Skylar J. Gaughan, Jae Sevelius, Rafael Lancelotta et al.

Transgender and gender-expansive individuals, particularly those who are Black, Indigenous, and People of Color, use psychedelics to heal from identity-based traumas such as racism and transphobia. Interviews with 20 participants revealed awareness of the Indigenous roots of psychedelic plant medicine and concerns that ongoing medicalization of psychedelics, shaped by colonization and structural racism, reproduces inequities in access and experience. Some participants opposed medicalization, linking it to racist and colonial dynamics. The findings suggest that culturally humble and ethically responsible models of psychedelic-assisted therapy are needed to promote health equity for transgender and gender-expansive people of color.

5-MeO-DMT Use in Humans: A Scoping Review of Peer-Reviewed Research

January 8, 2026 Michael Esposito, Ana M Ortiz Bernal, Alan K. Davis et al. preprint

A scoping review of 33 peer-reviewed studies on 5-MeO-DMT use in humans found that most interventional studies (13 of 15) used inhalation administration, though dosages and dosing regimens varied widely. Common outcomes measured include cognition, depression, post-traumatic stress disorder, and anxiety. The review highlights large heterogeneity in study design, dosing, and support, and suggests future research should explore different routes of administration and include more neuroimaging, qualitative, and longitudinal data.