Mental health outcomes following a psilocybin session within Oregon's state-regulated model: a naturalistic study
Pre-print posted on medRxiv — March 1, 2026.
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Authors
Amanda Gow, MS, LPC-a¹ · Emily Shih, PhD² · Ryan Reid, BS¹ · Jimmy J. Qian, MS² · Charan Mellor, MA¹ · Lynne Alison McInnes, MD² · Robin Carhart-Harris, PhD³ · Jennie N. Davis, PhD¹,⁴
¹ Bendable Therapy, Bend, Oregon, USA
² Osmind, San Francisco, California, USA
³ Weill Institute for Neurosciences, University of California San Francisco, San Francisco, California, USA
⁴ Center for Health Systems Effectiveness, Oregon Health & Science University, Portland, Oregon, USA
Corresponding author: Jennie N. Davis, PhD — Bendable Therapy, PO Box 1229, Bend, OR 97709 — jdavis@bendabletherapy.org — 541-408-0790
Abstract
Background: In 2020, Oregon became the first U.S. state to establish a regulated framework for adults to access psilocybin services using naturally-derived mushroom products. No studies have examined mental health outcomes among individuals receiving psilocybin in this context.
Aims: To evaluate changes in self-reported symptoms of depression, anxiety, and well-being 30-days post-psilocybin session under the Oregon state-regulated model, and document session-related adverse events and doses consumed.
Methods: This was a naturalistic study (March 2024–April 2025) among adults ≥21 years participating in a legal psilocybin services program. Online surveys were completed pre-session, 1-day, and 30-days post-session. Primary outcomes were change in depression, anxiety, and well-being symptoms pre-session to 30-days post-session evaluated using linear mixed-effects models (random effect: timepoint; fixed effects: sex, concurrent psychiatric medication use, age, session dose [total psilocybin equivalents, TPE, mg: psilocybin mg + 1.39 × psilocin mg]). Adverse events (e.g., hallucinogen persisting perception disorder [HPPD]) were assessed at 1-day and 30-days post-session.
Results: Participants (n=88; median age 43 years; 52% male) were predominantly Oregon residents (53.4%), psychedelic-experienced (64.8%), and concurrently using psychiatric medication (46.6%). All outcomes improved significantly at 30-days post-session (p<0.001), including in sensitivity analyses stratified by concurrent psychiatric medication usage (p<0.001 all outcomes, both groups). Two participants (2.3%) reported symptoms consistent with HPPD at 1-day post-session, but none at 30-days. Mean dose was 27.8 mg (SD 8.2) TPE.
Conclusions: Psilocybin sessions delivered under the Oregon regulatory model were associated with clinically meaningful improvements in depression, anxiety, and well-being 30-days post-session, supporting therapeutic effectiveness of legal psilocybin services.
Keywords: psilocybin, Oregon, depression, anxiety
Introduction
Psilocybin has emerged as a promising therapeutic intervention for mental health disorders, including depression and anxiety (Carhart-Harris et al., 2016, 2018; Dorczok et al., 2025; Goodwin, Aaronson, et al., 2023; Goodwin et al., 2022; Griffiths et al., 2016). As a naturally occurring psychoactive alkaloid found in certain species of mushrooms, once ingested, psilocybin is converted to psilocin to produce its characteristic psychedelic effects by acting on serotonin receptors (e.g., 5-HT2A) (Passie et al., 2002). These neuropharmacological actions are thought to underlie the improvements in mental health symptoms observed across controlled clinical trials and naturalistic observational studies (Calnan et al., 2025; Carhart-Harris et al., 2021; Compass, 2025; Davis et al., 2021; de la Salle et al., 2024; Goodwin, Aaronson, et al., 2023; Goodwin et al., 2022; Griffiths et al., 2016; Irrmischer et al., 2025; Nygart et al., 2022; Raison et al., 2023; Ross et al., 2016; von Rotz et al., 2023).
Most psilocybin clinical trials enroll highly selective samples under tightly controlled conditions, typically excluding individuals with complex psychiatric diagnoses or active psychiatric medication use, and administering synthetic psilocybin within standardized dosing protocols (Carhart-Harris et al., 2021; Davis et al., 2021; Griffiths et al., 2016; Raison et al., 2023; Ross et al., 2016; von Rotz et al., 2023). Only one trial has used a natural mushroom formulation to examine impacts of psilocybin on alcohol use disorder, with findings highlighting the therapeutic potential of natural mushroom formulations (Jensen et al., 2025). Naturalistic studies introduce greater variability in participants' medical and psychiatric histories, session formats, and psilocybin source (often whole fruit mushrooms), yet still demonstrate improvements in depression, anxiety, and well-being (Calnan et al., 2025; de la Salle et al., 2024; Irrmischer et al., 2025; Morton et al., 2023; Nygart et al., 2022; Tap et al., 2025). However, additional research bridging controlled clinical efficacy trials and real-world effectiveness is needed to understand psilocybin's mental health benefits in diverse, community-based populations.
In 2020, Oregon voters approved Measure 109, establishing the first regulated psilocybin services model in the United States and globally. These services are administered by the Oregon Health Authority (OHA) through its Oregon Psilocybin Services (OPS) section (Oregon Health Authority, n.d.). Oregon's non-medical model permits adults aged 21 years and older to access psilocybin by consuming products derived from whole fruit mushrooms (Psilocybe cubensis) at licensed service centers under the supervision of licensed facilitators (Oregon Health Authority, 2024). The model does not require a medical diagnosis, prescription, or clinical referral, despite mental health applications being common reasons for psilocybin use (Dorczok et al., 2025). In 2025, statewide aggregate data released under Senate Bill 303 began providing basic information, including demographics, psilocybin dosages, and session types. However, these data do not include clinical outcomes or follow-up assessments, limiting insight into the model's therapeutic effectiveness.
To address this gap, this study aimed to evaluate changes in self-reported symptoms of depression, anxiety, and well-being following a psilocybin session under Oregon's regulated model, and document session-related adverse events and psilocybin doses consumed. Predictors of session dosage were additionally explored to understand potential correlates of dosing decisions (e.g., participant characteristics, mental health history). Characterizing who uses psilocybin services and with what outcomes is critical to understanding the benefits and limitations of Oregon's regulated framework.
Methods
Setting and participants
This prospective, naturalistic study (March 2024–April 2025) was integrated into an existing Oregon legal psilocybin services program at Bendable Therapy ("Bendable"). Oregon regulatory minimums require one facilitator-client preparation session 24-hours in advance of a psilocybin administration session and to offer an optional integration session post-administration (Oregon Health Authority, n.d.). Bendable enhanced the Oregon requirements by including additional screening and support sessions (Figure 1). Eligibility requirements for legal psilocybin services are: aged 21 years or older, no lithium use in the past 30 days (due to seizure risk (Nayak et al., 2021)), no active psychosis, no active suicidal or homicidal ideation, not pregnant or breastfeeding [Bendable only] (Oregon Health Authority, 2024). During the study period, all individuals who attended the virtual interview (Figure 1) and met eligibility criteria were invited to the study and to complete the written informed consent. No compensation was provided to study participants. WCG Institutional Review Board approved this study.
Procedures and measures
A pre-session screening application (completed on average 75 days prior to the psilocybin administration session) collected demographics, medical, mental health, psychedelic use histories, medication usage, and validated scales assessing self-reported symptoms of depression (Patient Health Questionnaire, PHQ-9), anxiety (Generalized Anxiety Disorder, GAD-7), and well-being (World Health Organization Well-Being Index, WHO-5) (Figure 1).
The PHQ-9 maps nine depression symptoms over the past two weeks onto the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, Text Revision criteria for major depressive disorder; items are scored on a 4-point Likert scale (0="not at all" to 3="nearly every day") (Kroenke et al., 2001). For this study, the PHQ-9 was modified to PHQ-8 by excluding the suicidal ideation item; scores were adjusted accordingly (Shin et al., 2019). The GAD-7 is a 7-item self-report scale assessing generalized anxiety severity over the past two weeks with items rated on a 4-point Likert scale (0="not at all" to 3="nearly every day") (Spitzer et al., 2006). The WHO-5 is a 5-item measure of subjective psychological well-being where participants rated positive mood states (e.g., feeling cheerful, relaxed, or energetic) over the past two weeks on a 5-point scale (0="at no time" to 5="all of the time") (Topp et al., 2015).
On the administration session day, before consuming psilocybin, participants completed the Imperial Psychedelic Predictor Scale (iPPS), a validated 8- (individual sessions) or 9-item (group sessions) multidimensional self-report instrument designed to predict acute features of the psychedelic experience across the domains of set, intention, and rapport; items were rated 0–100 (Angyus et al., 2024). Consumed psilocybin and psilocin doses (mg) were recorded.
A survey emailed to participants 30-days post-session (completed on average 34 days post-session) included follow-up PHQ-8, GAD-7, and WHO-5 assessments, integration session attendance (a post-session participant-facilitator meeting to discuss and process the psilocybin session), and collected information on adverse events by assessing lingering unpleasant psychological effects attributed to the psilocybin session (i.e., anxiety, existential struggle, social disconnection, depersonalization/derealization) (Schlag et al., 2022), and assessed symptoms of Hallucinogen Persisting Perception Disorder (HPPD), a condition of enduring, distressing visual perceptions post-psychoactive substance intake (also assessed in a survey sent 1-day post-session) (Figure 1). HPPD symptoms attributed to the psilocybin session and not due to other medical or mental health conditions may be candidates for HPPD diagnosis (Zhou et al., 2025). For participants completing two sessions within the follow-up period (e.g., weeklong retreats), data were collected according to the first session only. Online assessments were completed via Jotform (Jotform Inc.).
Participants completed individual or group facilitator-supervised psilocybin sessions at licensed service centers following Oregon regulations (Oregon Health Authority, n.d.), and Bendable's protocols were not altered for this study. Psilocybin was consumed as whole mushrooms or tea made with ground whole mushrooms. Session dosing followed Bendable's protocol of a total dose of 20–30 mg psilocybin including optional 'booster doses,' or additional offered approximately 1-hr after the initial dose. Per Oregon rules, participants may request lower or higher doses (up to 50 mg) (Oregon Psilocybin Services, 2025, n.d.).
Statistical analysis
Participant pre-session characteristics are presented as medians (range) or frequencies (proportions). Primary outcomes were change in mental health status from pre-session to 30-days post-session using the PHQ-8, GAD-7, and WHO-5 scales.
Scores for the PHQ-8 (0–24) were summed, and cut-points of 5, 10, 15, and 20 denoted mild, moderate, moderately severe, and severe depression respectively; scores ≥10 indicated clinically significant depression (Kroenke et al., 2001). GAD-7 scores (0–21) were summed with cut-points of 5, 10, and 15 denoting mild, moderate, and severe anxiety respectively, with ≥10 indicating clinically significant anxiety (Spitzer et al., 2006). WHO-5 scores (0–25) were summed with scores <13 indicating poor well-being. The PHQ-8, GAD-7, and WHO-5 demonstrated strong internal consistency measured with Cronbach's alpha (PHQ-8: α=0.87 pre-session and 30-days post-session; GAD-7: α=0.91 pre-session and α=0.89 30-days post-session; WHO-5: α=0.96 pre-session and α=0.93 30-days post-session).
Per Oregon regulations, mushrooms were grown, processed, and potency-tested for analyte content (psilocybin and psilocin) in Oregon licensed facilities; product packaging listed analyte content in milligrams per gram of whole mushroom (Oregon Psilocybin Services, n.d.). Oregon regulations define dose by psilocybin content; because psilocybin rapidly converts to its pharmacologically active form of psilocin once ingested (Passie et al., 2002), Bendable calculates dose as Total Psilocybin Equivalents (TPE = psilocybin mg + 1.39 × psilocin mg), a metric assuming complete conversion of psilocybin to psilocin based on molecular weight (MacCallum et al., 2022). We report both TPE and psilocybin dose.
We used separate linear mixed effects models using the 'lme4' package in R to evaluate changes in outcomes across two timepoints (means, SE). Timepoint was modeled as a categorical variable (pre-session as reference), with fixed effects of birth sex (male/female), age (years), concurrent psychiatric medication use (yes/no), and dose (TPE, mg). Participant-level random intercepts and slopes accounted for individual differences in pre-session symptom levels and change over time. Prior to analyses, we evaluated covariate collinearity and excluded the session type variable (group vs. individual) due to strong correlation with TPE. Effect sizes 30-days post session (relative to pre-session) were calculated using Cohen's d. This was calculated by dividing the estimated marginal mean differences by the pooled standard deviation, which incorporated both the residual variance and the random intercept variance from the fitted model. Effect sizes were classified as small (0.20–0.49), moderate (0.50–0.79), large (≥0.80), or very large (≥1.2) (Cohen, 1992). Model fit was summarized using marginal and condition R² to indicate variance explained by fixed effects and by the full model, respectively. A post-hoc simulation-based power analysis (α=0.05) indicated approximately 100% power for large effects and 89% for small effects.
Sensitivity and exploratory analyses
In a sensitivity analysis, we repeated the adjusted models substituting TPE with psilocybin dosage to assess robustness to an alternative dose specification. In a second analysis to assess whether findings were driven by participants with additional dosing, we restricted the sample to participants who completed a single session during the study period (n=75), excluding those with multiple sessions (n=13). In a third analysis, we stratified the sample by concurrent psychiatric medication use and repeated the adjusted models separately among participants with (n=41) and without (n=47) pharmacotherapy to descriptively assess whether patterns of outcomes were consistent across medication status.
To explore correlates of dosing decisions, we used univariate linear regression models to examine predictors of session dose (TPE). Predictors included pre-session PHQ-8, GAD-7, and WHO-5 scores; age; birth sex; most commonly reported diagnoses: depression, anxiety, post-traumatic stress disorder (PTSD); concurrent psychiatric medication use; prior psychedelic experience (Irrmischer et al., 2025). In a separate multivariate regression model, iPPS subscales were entered simultaneously to assess their independent contributions to TPE. Given these analyses' exploratory nature, p-values were not adjusted for multiple comparisons.
Analyses were conducted using R/R Studio version 4.4.2 (R Foundation), and included only participants who completed all pre- and post-session surveys; we set statistical significance at p<0.05.
Results
Participant characteristics
During the study period, n=311 screening applications were received. Of these, n=126 individuals met eligibility criteria for psilocybin services and were invited to participate, n=91 enrolled, and n=88 completed all study components and comprised the analytic sample. Participants (n=88) ranged in age from 22–79 years (median: 43 years), were approximately balanced by birth sex and gender identity (n=46, 52.0% male; n=44, 50.0% male-identifying), and were predominantly White (n=77, 87.5%), educated (n=74, 84.1% with higher education), and employed (n=59, 67.1%), with only 22.7% (n=20) reporting annual household income below $50,000 (Table 1). Most participants were Oregon residents (n=47, 53.4%) and 15.9% (n=14) were military veterans. Depression (n=45, 51.1%), anxiety (n=37, 42.0%), and PTSD (n=17, 19.3%) were the most reported mental health diagnoses. Almost half (n=41, 46.6%) reported concurrent use of psychiatric medications (medication type and dosage were not systematically collected) and participation in mental health therapy (n=50, 56.8%). The majority (n=57, 64.8%) had prior psychedelic experience, and cost was the most frequently reported barrier to seeking psilocybin services (n=41, 46.6%) (Table 1). Most participants completed individual sessions (n=50, 56.8%) rather than group sessions (n=38, 43.2%), and 80.0% (n=70) completed at least one integration session during follow-up.
Mental health outcomes after a psilocybin session
We examined whether participation in a psilocybin session was associated with changes in mental health outcomes. Pre-session, 69.3% (n=61) of participants reported mild to severe depression symptoms, 67.0% (n=59) reported mild to severe anxiety symptoms, and 93.2% (n=82) reported low or very-low sense of well-being, reflecting clinically significant symptom levels across all measures (Table 2). At approximately 30-days post-session, improvements were observed across measures, with 61.4% (n=54) of participants reporting minimal depression, 70.5% (n=62) reporting minimal anxiety, and 64.8% (n=57) reporting normal levels of well-being.
Modeling results similarly reflected significant improvements in mental health outcomes over time (Figure 2, Table 3). PHQ-8 and GAD-7 mean scores significantly decreased pre-session to 30-days post-session, suggesting robust declines in depression and anxiety symptoms: PHQ-8 score change of −4.63 (0.57 SE) points; p<0.001; d=0.90 (95% CI: 0.68, 1.12) large; GAD-7 score change of −4.85 (0.57) points; p<0.001; d=1.04 (0.80, 1.17) large. WHO-5 well-being scores also improved at follow-up with a score change of +10.67 (0.59) points; p<0.001; d=−2.14 (−2.38, −1.90) very large, indicating significant gains in well-being. Of the covariates examined, only concurrent psychiatric medication use was positively associated with post-session PHQ-8 scores (p=0.040).
Sensitivity analyses, one substituting psilocybin for TPE as the dose covariate in all outcomes models and another limited to participants who completed a single administration session (n=75), yielded results consistent with the primary analysis, with no change in the direction or magnitude of timepoint effects (Supplemental Tables 2 and 3). In a third sensitivity analysis, results from stratified models by concurrent psychiatric medication use were largely consistent with those from the full cohort, with significant post-session improvement across all outcomes observed in both groups (p<0.001) (Supplemental Table 4). Overall, these findings support the robustness of the primary results.
Post-session adverse events
Participants (n=35, 39.7%) reported symptoms of HPPD at 1-day post-session, and two (2.3%) indicated these symptoms caused significant distress and were attributed to the psilocybin session, potentially meeting diagnostic HPPD criteria. Fewer participants (n=16, 18.2%) reported HPPD symptoms at 30-days post-session, with none reporting the symptoms caused significant distress. Three (3.4%) participants reported lingering negative effects of the psilocybin experience at 30-days post-session, noting increased feelings of anxiety or fear, existential struggle, social disconnections, and difficulty coping with family members.
Session dose and exploratory analyses predicting psilocybin session dose
The average dose (TPE) consumed by participants was 27.8 mg (8.2 SD), and was 24.3 mg (8.3 SD) when restricted to psilocybin (Table 4). In exploratory analyses examining predictors of dose (TPE), the only significant predictor was concurrent use of psychiatric medications, which was associated with greater administered dose (b=3.44, p<0.05; Supplemental Table 5); these participants received an average dose of 29.6 mg TPE (26.2 mg TPE for those not taking psychiatric medications). No iPPS subscales were significantly associated with dose (Supplemental Table 6).
Discussion
This prospective, naturalistic study presents the first results examining the impact of psilocybin on mental health outcomes within Oregon's state-regulated model. We found that at 30-days post-psilocybin session, participants reported significant reductions in depression and anxiety symptoms and significant improvements in well-being. These benefits were observed in a community-based population that included individuals with multiple psychiatric diagnoses and those actively using psychiatric medications, populations often excluded from research of psilocybin's impact on mental health. Our findings suggest that psilocybin services delivered within a structured and supportive framework can produce therapeutic benefits. This translational evidence is needed to inform policy and clinical implementation as jurisdictions worldwide consider regulated psilocybin programs.
As a therapeutic intervention, psilocybin is particularly effective when combined with therapeutic support (Carhart-Harris et al., 2016, 2018; Dorczok et al., 2025; Griffiths et al., 2016), though therapeutic support is not uniformly included in studies of psilocybin's impact on mental health (Dorczok et al., 2025). The results of this study were achieved under an enhanced, supportive model, relative to the minimum requirements set forth under Oregon's Measure 109, through incorporating comprehensive screening, multiple preparation sessions, and structured integration support with licensed facilitators of which many held additional clinical health licenses. Such enhancements potentially influenced the overall significant improvements in mental health outcomes among study participants, including limited adverse events and few reports of psychedelic harm, which is consistent with prior studies (Evans et al., 2025). Research also indicates that integrative psychological support and facilitated processing after psychedelic-assisted sessions increase the likelihood of sustained benefits (Gorman et al., 2021; Greń et al., 2024).
Study participants demonstrated clinically significant improvements in self-reported symptoms of depression, anxiety, and well-being. At 30-days post-session, 65% of participants reported normal well-being despite approximately one-third continuing to report mild to severe symptoms of depression or anxiety. Because the WHO-5 captures mental and emotional domains related to psychological flexibility and adaptive functioning (Topp et al., 2015), these findings may suggest a growing capacity for change and emerging emotional resilience, which are domains of functioning that individuals may particularly value (Connell et al., 2014). Other studies of the impacts of psilocybin on well-being likewise reported increased well-being or life satisfaction post-psilocybin session (Mans et al., 2021; Wiepking et al., 2023).
Consistent with our results, a recent naturalistic study of U.S. veterans attending psychedelic retreats outside the U.S. documented clinically significant reductions in depression with the PHQ-9 one-month post-psychedelic session, though not all participants consumed psilocybin as the psychedelic substance (some received ayahuasca) (Calnan et al., 2025). A naturalistic study from Germany similarly reported significant improvements in depression (PHQ-9) and anxiety (GAD-7) symptoms following a psilocybin session, with an approximate 25 mg psilocybin dose from fresh mushrooms, though follow-up timepoints were at 1 week and 3 months (Irrmischer et al., 2025). This study also included participants with multiple psychiatric diagnosis, which is less commonly studied (Aaronson et al., 2024; Rosenblat et al., 2024). In our study, nearly two-thirds of participants had mental health diagnoses, many concomitant, and few experienced post-session adverse events, adding to the extant evidence that psilocybin services can be safely delivered to populations experiencing a range of mental health conditions in real-world settings.
In clinical trials, dose is standardized and often fixed at 25 mg of synthetic psilocybin (Back et al., 2024; Carhart-Harris et al., 2021; Goodwin, Croal, et al., 2023; Goodwin et al., 2022; Rosenblat et al., 2024), including the recent COMPASS Pathways Phase 3 COMP005 trial (Compass, 2025). The average doses administered in our study (27.8 mg TPE, 24.3 mg psilocybin) were comparable to trials' standard dose, and outcomes were similar whether assessed by TPE or psilocybin content alone. The novel dosing protocol described in our study, which accounts for both psilocybin and psilocin content, provides a useful framework for other states developing regulated programs utilizing natural-derived mushroom products, and may inform policy decisions regarding maximum dose limits. While Oregon's legal maximum is 50 mg, this study demonstrated meaningful improvements in outcomes with limited adverse events at an average dose below 30 mg TPE, suggesting that lower doses may be both effective and well-tolerated in real-world settings. Additional research is needed to confirm both safety and efficacy of this dosing practice, and among a greater diversity of populations than was included in this study.
Individuals taking psychiatric medications are often excluded from clinical trials to reduce the risk of a psilocybin blunting effect, allow for uniform dosing, and minimize the risk of serotonin toxicity (MacCallum et al., 2022; Malcolm and Thomas, 2022). Two psilocybin clinical trials have examined the impacts on participants taking psychiatric medications, and found reduced depressive symptoms (Goodwin, Croal, et al., 2023), and reduced adverse effects of psilocybin (Becker et al., 2022). We found that participants using psychiatric medications consumed modestly higher average doses. Sensitivity analyses restricted to this subgroup yielded results consistent with the main findings, suggesting concurrent psychiatric medication use did not substantially alter treatment response. While this may suggest that psilocybin services using whole-fruit mushroom products may be effective at improving mental health outcomes without requiring psychiatric medication discontinuation, additional controlled research examining psychiatric medications and doses, and explicitly testing moderation effects, is needed (Erritzoe et al., 2024).
Strengths and limitations
This study has several notable strengths. It represents the first systematic evaluation of mental health outcomes following psilocybin administration within the first regulated framework in the US, and the first to quantify both psilocybin and psilocin content in administered doses. This real-world study design provides evidence of effectiveness in naturalistic settings with individuals with mental health complexities thereby offering a realistic assessment of treatment benefits that complement traditional efficacy data (McInnes et al., 2024). Rigorous data collection and participant follow-up yielded near-complete retention, with data from only three participants excluded. Within-person pre–post assessments reduced between-person confounding, and the use of widely implemented validated instruments for depression, anxiety, and well-being supports comparison with prior studies.
Limitations of the study include its small sample size and the predominance of participants residing in Oregon, impacting its generalizability. However, the study was adequately powered to detect medium to large effect sizes in change in mental health symptoms, supporting the robustness of the observed results. As an observational study without a control group, causality cannot be inferred, and placebo effects, self-selection bias, expectancy bias, and unmeasured confounding factors (such as influential participant lifestyle or situational changes during the study period) cannot be ruled out (Lewis et al., 2026). Also, the follow-up period was limited to 30-days post-session; although this duration aligns with many clinical trials and observational studies (Calnan et al., 2025; Davis et al., 2021; Griffiths et al., 2016; Rosenblat et al., 2024), longer-term effects remain to be determined and should be investigated in future studies conducted within Oregon's regulated model (Korthuis et al., 2024).
Conclusion
In this prospective, naturalistic study, we found that carefully screened participants who underwent a supervised psilocybin session within Oregon's regulated framework and consumed naturally-derived mushroom products experienced significant improvements in depression, anxiety, and overall well-being with few adverse events, even among those with concurrent use of psychiatric medications and complex mental health histories. These findings demonstrate that psilocybin can be delivered safely and effectively in real-world settings, broadening the potential accessibility of psilocybin services as a tool to bridge clinical and community care. For Oregon, these data strengthen confidence in the state's pioneering regulatory framework, offering data-driven guidance for establishing standardized practices in supportive psilocybin service frameworks, while advancing policy goals to safely expand this emerging mental health field.
Acknowledgments
We thank the participants for their time, trust, and willingness to share their experiences. We also acknowledge the valuable contributions of the Bendable Therapy team members who supported data collection: Brooke Harralson, River Jenkins, Sam Georgi, and Matt Hailey. These individuals did not receive additional compensation for these contributions.
Author contributions
A.G., R.R., J.J.Q., L.A.A., R.C.H., and J.N.D. designed the study. A.G., R.R., C.M., and J.N.D. collected the data. E.S. conducted data analysis. A.G., E.S., R.R., J.J.Q., and J.N.D. interpreted the data. A.G., E.S., R.R., and J.N.D. wrote the initial draft of the manuscript. All authors critically reviewed the manuscript and approved the final draft. J.N.D. is accountable for all aspects of the study and manuscript.
Statements and declarations
Ethical Considerations: The WCG Institutional Review Board approved our study (approval confirmation: 45583966) on March 15, 2024.
Consent to Participate: Participants gave written consent for review and signature before completing any study components.
Declaration of Conflicting Interest: A.G. reported receipt of honoraria for presentations at University of Louisiana, Monroe. R.R. reported ownership of Aboveground Services and receipt of honoraria for consulting with Healing Advocacy Fund and for presentations with Soundmind. J.J.Q. reported owning shares in Osmind. C.M. reported employment with Aboveground Services. R.C.H. reported advisor roles for Tryp Therapeutics, Osmind, Red Light Holland, and Otsuka, and receipt of honoraria for lectures, presentations, or educational events for HMP Global, Aspen Institute, Psychedelic Science IRAS, Heartmind, Clearmind, and Psychedelic Coaching Institute. No other disclosures were reported.
Funding Statement: The authors disclosed receipt of the following financial support for the research, authorship, and/or publication for this article: This work was financially supported in part by the Jurvetson Foundation. The funder had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; preparation, review, or approval of the manuscript; and decision to submit the manuscript for publication.
Data Availability: The datasets generated during and/or analyzed during the current study are available from the corresponding author upon reasonable request.
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