Abstract
Background and aims
Scientific interest in the therapeutic potential of psychedelics has been experiencing significant growth. Understanding the perceptions of psychedelic assisted psychotherapy (PAP) among health professional, patients, and the public is essential to guide future research objectives, trial protocols, and identify any barriers to future implementation.
Methods
A comprehensive search of the databases (Medline, EMBASE, PSYCHinfo, SCOPUS, and Web of Science) was conducted on the 29th of November, 2022. This review included cross-sectional, longitudinal, and quasi-experimental studies published in peer-reviewed journals exploring perceptions of PAP among the three stakeholder groups. Studies were limited to English-language and the years 2012–2022. The protocol and review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analysis (PRISMA) guidelines.
Results
The sample consisted of 29 studies, including n = 17 health professional, n = 6 patients, and n = 6 public. Broadly, knowledge of PAP was low among all three stakeholder groups. There was mixed to positive belief in the therapeutic potential of psychedelics, with male gender, younger age, and personal psychedelic experience/knowledge being key predictors of more favourable views. The majority of findings reported strong endorsement of further research. Consistent themes were identified surrounding concerns about legal status, funding, access, side-effects, and implementation.
Conclusion
The evaluated research indicates a need for further research that will provide clarity about safety and elucidate how PAP may be implemented in public health settings. Further education of health professionals and the public should be a priority.
Introduction
This systematic review examines perceptions of psychedelic-assisted psychotherapy (PAP) among three stakeholder groups: health professionals, patients, and the public. Attitudes across these groups are likely to be highly variable. Health professionals are responsible for patient education, referral, and research conduct. Patients make decisions to participate in trials depending on their trust in the treatment and how efficacious or risky they perceive it to be, and the general public informs social norms and can influence drug policy. Understanding these unique perspectives is imperative for future research, trial development, and, ultimately, the utilization of psychedelic-assisted psychotherapy.
There is growing evidence for the efficacy of psychedelic-assisted psychotherapy. A recent systematic review by Maia, Beaussant, and Garcia (2022) reported on twenty studies assessing the potential of PAP in patients with serious illnesses. The evaluated evidence indicated positive effects, especially in relation to symptoms of a psychological or spiritual nature. However, the average sample size across these studies was only 32, raising questions about statistical power and generalisability. Similarly, Reiff et al. (2020) reported on the efficacy of MDMA and psilocybin in treating symptoms of PTSD and depression, but noted that confounders, patient bias, and challenges associated with blinding remain. Recent articles provide a valuable analysis of methodological problems associated with psychedelic trials (Muthukumaraswamy et al., 2021, 2022). With this caveat in mind, initial evidence indicates these treatments have the potential to generate advancements in psychological intervention and require further investigation.
An issue of relevance to this treatment is barriers to access. In most regions, psychedelics are classified as Schedule I drugs, defined as having no medical use and a high potential for risk and abuse. This restricts research in the area (Nutt, King, & Nichols, 2013) through exhaustive regulations prohibiting PAP delivery. However, some countries (e.g., Canada) have authorized certain health professionals to hold exemptions to these restrictions. In New Zealand, Section 29 of the Medicines Act 1981 allows medical practitioners to prescribe unapproved medicines such as Class A drugs with special permission (Medicines Act 1981, s. 29). This legislation recognizes the potential of otherwise illegal substances to be used in a medical context with informed consent and safety precautions. Nonetheless, legislation continues to be a barrier to access, with the misalignment of law and actual harm likely contributing to negative perceptions of psychedelics and the perpetuation of stigma among all three stakeholder groups.
The stigmatization of psychedelics following the historical context of the “war on drugs” is well established. The explosion of Western psychedelic use can be traced back to the 1960s and is often linked to the counterculture movements of the time. The momentum with which these movements grew, combined with highly sensationalized media coverage, led the Nixon administration to declare a war on drugs to mitigate the perceived threat to social order. Psychedelic drug use was transformed into a moral issue, with drastic law enforcement measures and prolific public campaigns portraying these substances as dangerous and harmful. These negative historical connotations likely still contribute to perceptions of psychedelics today, despite having limited or no scientific foundation (Schlag et al., 2022).
The last twenty years have marked the “third wave” of research exploring the potential of psychedelics. This research has gained traction to the point where mainstream media can oversimplify psychedelics as miracle cures with titles such as “Psychedelic Drugs: The Miracle Drugs of the 21st Century” (Nielson, 2017). The portrayal of beneficial outcomes is often simplistic and scientific findings can be misrepresented (Carhart-Harris et al., 2018; Yaden et al., 2022). This rhetoric may downplay the importance of exercising caution and represents yet another potential source of misinformation, with the ability to produce unrealistic expectations about the benefits of psychedelics.
Objectives
It is unclear how the impact of legality, historical stigma, and contemporary media might impact the perspectives of health professionals, patients, and the public toward PAP. Understanding these stakeholder perspectives is imperative to inform policy development, regulations, treatment protocols, and best practice guidelines while considering patient safety, equitable access, and ethical standards. Thus, this systematic review aimed to examine perceptions of PAP among these stakeholder groups. Specifically:
What knowledge do health professionals, patients, and the public have about PAP?
What are the potential benefits or perceived appeal of PAP among these stakeholder groups?
What are the perceived barriers or concerns associated with PAP?
Methods
The review was conducted according to the Preferred Reporting Items for Systematic Review and Meta-Analyses (PRISMA) guidelines (Page, McKenzie, et al., 2021). The protocol was prospectively registered in PROSPERO 2022 CRD42022382430.
Eligibility criteria
Studies were limited to English-language peer-reviewed articles and student theses published between 2012 and 2022. Full eligibility criteria are outlined in Table 1. Studies were excluded if they were intervention studies, solely related to recreational use or physical outcomes, or did not include one of the stakeholder groups.
Inclusion/exclusion criteria
| Inclusion | Exclusion | |
| Participants | Health professionals, general public, patient groups, psychedelic naive and experienced | |
| Study Design | Cross sectional, survey, interview, quasi-experimental | Review articles |
| Outcome | Perceptions or attitudes towards psychedelic assisted psychotherapy | Efficacy of psychedelics treating physical symptoms |
| Substance of Interest | Psilocybin, LSD, DMT, Mescaline, Ketamine, MDMA, Ibogaine, Salvinorin | |
| Publication | Peer reviewed journal articles, student theses | Conference abstracts |
QuADS Scores and means by stakeholder group
| Group | Reference | Total QuADS score | Percentage (%) |
| Health Professionals | Barnett et al. (2022) | 26 | 66.7 |
| Barnett et al. (2018) | 25 | 64.1 | |
| Beaussant et al. (2020) | 38 | 97.4 | |
| Beaussant et al. (2021) | 36 | 92.3 | |
| Brennan et al. (2021) | 34 | 87.2 | |
| Callon et al. (2021) | 30 | 76.9 | |
| Davis et al. (2022) | 34 | 87.2 | |
| Earleywine et al. (2022) | 33 | 84.6 | |
| Hearn et al. (2022) | 34 | 87.2 | |
| Levin et al. (2022) | 35 | 89.7 | |
| Luoma et al. (2022) | 34 | 87.2 | |
| Mayer et al. (2022) | 36 | 92.3 | |
| Meyer et al. (2022) | 20 | 51.3 | |
| Page, Rehman, et al. (2021) | 38 | 97.4 | |
| Reynolds et al. (2021) | 38 | 97.4 | |
| Reynolds et al. (2022) | 39 | 100 | |
| Winkler & Csémy (2014) | 37 | 94.9 | |
| Total (mean) | 33.6 | 86.2 | |
| Patients | Corrigan et al. (2022) | 32 | 82.1 |
| Glynos, Pierce, et al. (2022) | 35 | 89.7 | |
| Harding et al. (2021) | 37 | 94.9 | |
| Jilka et al. (2019) | 37 | 94.9 | |
| Jilka et al. (2021) | 38 | 97.4 | |
| Spriggs et al. (2021) | 34 | 87.2 | |
| Total (mean) | 35.5 | 91.0 | |
| Public | Glynos, Fields, et al. (2022) | 38 | 97.4 |
| Grabski et al. (2022) | 34 | 87.2 | |
| Kruger et al. (2022) | 37 | 94.9 | |
| Mathai et al. (2021) | 31 | 79.5 | |
| Žuljević et al. (2022) | 38 | 97.4 | |
| Wildberger et al. (2017) | 20 | 51.3 | |
| Total (mean) | 33 | 84.6 |
Search strategy
We conducted electronic searches on 29th November 2022 of the following databases: Medline, EMBASE, PSYCHinfo, SCOPUS, and Web of Science.
Figure 1 indicates the search terms that were used for each database using the title, abstract, and MESH fields.
Selection process
Search results were exported to Endnote, and duplicate articles were removed. The remaining articles' titles and abstracts were screened by two reviewers (AW, MF) using the inclusion/exclusion criteria. Approximately 20% of the records were screened by both reviewers. Any uncertainties were discussed with a third reviewer (LR). All three reviewers confirmed the final inclusion of articles into the review.
Upon assessing records, it was determined that longitudinal and quasi-experimental study designs produced results addressing our key outcomes and needed to be included. This was a revision to the initial inclusion criteria. We also expanded the terminology as “psychedelic-assisted psychotherapy” was not consistently used. Articles referring to “psychedelic-assisted therapy” also encapsulated the therapeutic use of psychedelics.
Data collection process
Each article's full text was retrieved for data extraction. Data were organised in an Excel Spreadsheet according to location, population, recruitment, methodology, results (appeal, perceived benefits, barriers to access, concerns, knowledge), abstract, and conclusion. Data were extracted by MF and reviewed by AW.
Data items
Data relating to attitudes and perceptions were separated into three categories: 1) appeal and perceived benefits, 2) barriers to access and concerns, and 3) knowledge. Not every article covered all key outcomes. Data on participant characteristics, such as psychedelic experience, was also sought.
Study risk of bias assessment
Study quality was assessed using the Quality Assessment with Diverse Studies (QuADS) tool, previously the QATSDD (Harrison, Jones, Gardner, & Lawton, 2021, pp. 1–20). The tool consists of 13 questions designed to assess the methodological quality and limitations of the studies, allowing for consistency in quality rating across qualitative, quantitative, and mixed-methods research. Two independent reviewers (AW, LR) assessed the quality of the included studies, with any discrepancies discussed and resolved after the appraisal was complete (see Table 2).
Synthesis methods
The extracted data were qualitatively synthesized to summarise relevant outcomes in a narrative review. It was not suitable to conduct a meta-analysis due to the heterogeneity across study types and outcomes.
Results
The database search returned 2,391 articles (see Fig. 2). Of these, 679 were duplicates and removed. The remaining 1712 articles were screened by title and abstract, resulting in the exclusion of 1,675 reports. A total of 37 full-text records were obtained and assessed for eligibility, resulting in the inclusion of 28 articles. All included article reference lists were checked for additional eligible records, which produced one extra, bringing the total number of articles included in the review to 29.
Articles primarily included data from populations based in the USA (18), UK (6), Canada (4), and New Zealand (2). The remaining articles focused on populations from Croatia, Czechia, and Ireland.
Most articles covered health professionals' perspectives (17), with six focussing on patients and six on the public. All articles were published in the last decade, with the bulk of research published in 2020 or later.
Health professionals
The articles focussing on health professionals covered a range of professions, including psychiatrists, doctors, psychologists, counsellors, ayahuasca ceremony leaders, healthcare support workers, and psychedelic integration therapists.
Knowledge
Thirteen of the health professional studies assessed knowledge, with most assessing self-reported knowledge and only one study using an objective measure of knowledge (Barnett, Beaussant, King, & Doblin, 2022). Broadly, health professionals had limited knowledge of PAP (Barnett et al., 2022; Davis, Agin-Liebes, España, Pilecki, & Luoma, 2022; Mayer, LeBaron, & Acquaviva, 2022; Meyer, Meir, Lex, & Soares, 2022; Page, McKenzie, et al., 2021; Reynolds et al., 2021), its therapeutic application (Barnett et al., 2022; Davis et al., 2022; Page, McKenzie, et al., 2021), and associated risks and benefits (Mayer et al., 2022). In Barnett et al. (2022), psychiatrists reported an incorrect overestimation of the prevalence of hallucinogen use disorder. Notably, Page, McKenzie, et al. (2021) reported that, compared to trained psychiatrists, trainees reported greater PAP knowledge due to greater exposure to psychedelic-focused research and lectures. Individuals with low knowledge reported relying on heuristics to inform their opinions, often gaining knowledge from media or news articles (Reynolds et al., 2021). One study made cultural comparisons between NZ and USA, finding that USA-based clinicians had greater awareness of psychedelics and PAP compared to those located in NZ (Reynolds et al., 2022).
In several studies, health professionals discussed the limitations in their understanding and a desire for further training (Davis et al., 2022; Page, McKenzie, et al., 2021; Reynolds et al., 2021). In one study, psychiatrists noted the importance of increasing the public's understanding and knowledge of psychedelic substances (Page, McKenzie, et al., 2021). Two of the studies described areas for training (Barnett et al., 2022; Mayer et al., 2022), including potential benefits of PAP, pharmacology, side effects, developing trust, spirituality, ethical integrity, and building proficiency in implementation. Finally, four studies included perspectives on therapist's own use of psychedelics, with therapists from the former Czechoslovakia reporting that their experimentation (while it was still legal pre-1974) was instrumental in their training and preparedness in working with patients (Winkler & Csémy, 2014). Beaussant, Tulsky, Guérin, Schwarz-Plaschg, and Sanders (2021) expressed support for therapists using psychedelics to facilitate training. However, counsellors in Hearn, Brubaker, and Richardson (2022) reported mixed views on the role of psychedelic use in training.
Appeal and perceived benefits
Eight articles investigated health professionals' perceived appeal and benefits of PAP. Greater psychedelic knowledge, being younger (Barnett, Siu, & Pope, 2018, 2022; Hearn et al., 2022; Luoma, Pilecki, Davis, & Smith, 2022), male (Barnett et al., 2018; Hearn et al., 2022; Luoma et al., 2022) and a trainee/student (Barnett et al., 2018; Hearn et al., 2022) were positively associated with appeal toward PAP, whereas, being a psychiatrist, counsellor, and longer professional experience were associated with unfavourable attitudes (Barnett et al., 2022; Hearn et al., 2022). In one sample, exposure to information created a shift from ‘hesitation’ to ‘cautious curiosity’ (Reynolds et al., 2021). Barnett et al. (2022) concluded that psychiatrists who had worked in research were more likely to see potential in psychedelic treatment and support medicinal psychedelic legalization. Cancer healthcare practitioners with research experience were more likely to refer patients to PAP trials than those without; however, they were also less likely to perceive its benefits (Reynolds et al., 2022). Finally, Luoma et al. (2022) found religiosity to be a predictor of attitudes, with religiously unaffiliated professionals expressing more positive perceptions of PAP than those who were religious.
A minority of papers touched on the existential and spiritual value of PAT. Advanced cancer and palliative care workers highlighted the nature of distress associated with a serious illness which is often overlooked by current interventions, expressing interest in the potential of PAP in this area (Beaussant et al., 2021; Mayer et al., 2022; Reynolds et al., 2021). Health professionals often framed PAP as novel and a source of hope for patients for whom “little else had worked” (Page, McKenzie, et al., 2021). Psychedelic healing practitioners spoke of psychedelic work as a platform for more openness and intimacy than conventional talk therapies (Brennan, Jackson, MacLean, & Ponterotto, 2021). Many health professionals acknowledged the rich indigenous knowledge and history behind the therapeutic use of psychedelics (Beaussant et al., 2021; Reynolds et al., 2021).
Psychiatrists in Levin et al. (2022) rated psilocybin and ketamine as safer and with greater therapeutic potential than substances such as alprazolam, methamphetamine, and alcohol. Conversely, psychologists in Davis et al. (2022) rated psychedelics as having the same comparative risk as alcohol, with opioids, cocaine, and lastly cannabis perceived as less risky. Participants in Meyer et al. (2022) held more positive attitudes towards medicinal cannabis than psilocybin.
Overall, articles indicated varying levels of acceptance from health professionals. While a majority reported interest in potential benefits, uncertainty around risks and effectiveness was also evident.
Barriers and concerns
Sixteen articles explored the perceived barriers and concerns of health professionals. The current legal status of psychedelic substances was noted as a challenge to PAP research and as impacting perceptions about the therapeutic use of psychedelics (Beaussant et al., 2021; Earleywine, Low, Lau, & De Leo, 2022; Levin et al., 2022; Page, Rehman, Syed, Forcer, & Campbell, 2021; Reynolds et al., 2021). A subset of psychiatrists in the US and UK criticized local drug policy or advocated for reform (Luoma et al., 2022; Page, Rehman, et al., 2021). For example, 77% of UK-based psychiatrists in Page, McKenzie, et al. (2021) believed that controlled or therapeutic use of psychedelics has a place in society. Among US-based psychiatrists, 90% of the sample moderately or strongly believed that the US federal government should fund research into the therapeutic potential of psychedelics (Barnett et al., 2022). Participants in the reviewed studies said further research into PAP was required (Barnett et al., 2018; Beaussant et al., 2020; Davis et al., 2022; Reynolds et al., 2021; Winkler & Csémy, 2014), with some studies making simple endorsements for further research (Barnett et al., 2018; Davis et al., 2022), and others outlining key priorities (Beaussant et al., 2021) or indicating that research needed more rigorous methodology akin to traditional drug trials to bolster safety concerns (Beaussant et al., 2020; Reynolds et al., 2021). Two studies noted that the current medical model may have limitations in its application to understanding PAP (Beaussant et al., 2021; Reynolds et al., 2021).
Several articles reported perceived risks associated with PAP, including potential psychiatric or neurocognitive risks (Barnett et al., 2018; Davis et al., 2022; Hearn et al., 2022). Between 30 and 40% of US-based psychiatrists (Davis et al., 2022) and counsellors (Hearn et al., 2022) believed that psychedelic use had cognitive and psychiatric impairment risks. Other health professionals highlighted their responsibility not to cause harm (Reynolds et al., 2021), with some mixed views on whether it is possible to eliminate all possible harms associated with PAP (Winkler & Csémy, 2014). Due to the perceived potency of the psychedelic experience, microdosing was suggested as a potential alternative to full-dose treatment. However, there were concerns that the reduced potency may be associated with reduced efficacy (Reynolds et al., 2021). In a quasi-experimental survey of psychologists' attitudes, participants were twice as likely to warn a potential client about the risks of a psychedelic retreat than a meditation retreat. They were also less open to PAP as compared to a medication-assisted (methadone or suboxone) treatment for people with substance use disorder (Davis et al., 2022).
Ceremonial ayahuasca leaders noted unique risks, including participants potentially misrepresenting themselves to gain access to a ceremony, lack of proper integration practices, or concomitant use of pharmaceuticals, illicit drugs, or alcohol (Callon, Williams, & Lafrance, 2021). Others indicated that although PAP may be beneficial for certain populations, there may be higher risk among other patient populations (Beaussant et al., 2020; Page, Rehman, et al., 2021), including those that may be receiving treatments that pose contraindications (Barnett et al., 2022; Reynolds et al., 2021). Ethical challenges associated with PAP were also noted, including heightened power differentials between therapist and participant, greater risk of transference and countertransference, concerns about embodiment or sexual expression, client vulnerability and reduced autonomy, as well as challenges associated with different availability needs compared to other therapy (Brennan et al., 2021; Earleywine et al., 2022).
Similarly, participants identified several implementation characteristics that differ from other therapeutic modalities. Beaussant et al. (2020) outlined essential features of PAP, such as preparation and integration, therapeutic alliance and boundaries, and education needs for patients, carers, and providers. Also noted were institutional requirements, including appropriate therapeutic settings, the need for interdisciplinary teams, and defining the training and certification requirements. In the context of these complexities, health professionals commonly reported concerns about the logistical demands of PAP, questioning how integration of PAP into other models of care would work in practice (Barnett et al., 2022; Beaussant et al., 2021; Brennan et al., 2021; Callon et al., 2021; Earleywine et al., 2022; Mayer et al., 2022; Page, Rehman, et al., 2021). UK-based psychiatrists stated they felt unprepared to participate in the delivery of PAP (Page, Rehman, et al., 2021), with many asking who would be responsible (Beaussant et al., 2020; Mayer et al., 2022; Page, Rehman, et al., 2021). Finally, proper patient and public education to ensure adequate preparedness (Beaussant et al., 2020; Callon et al., 2021) and buffer unrealistic hopes (Earleywine et al., 2022) were reported as a priority.
Patients
Six of the 29 studies included the perspectives of patients. This included mental health service users and patients with specific diagnoses such as eating disorders, depression, and fibromyalgia.
Knowledge
Four articles explored patient self-reported knowledge of PAP, with knowledge generally low. As might be expected, patients with previous psychedelic experience reported greater awareness, interest, and knowledge than those without (Corrigan et al., 2022; Glynos, Pierce, Davis, McAfee, and Boehnke, 2022). Patients endorsed a need for more information about interventions (Harding et al., 2021; Jilka et al., 2019) and noted concerns about health professionals' lack of PAP knowledge, reporting feeling misunderstood and guilty when disclosing their personal use of ketamine to treat depression (Jilka et al., 2019).
Appeal and benefits
Five articles addressed the perceived appeal or benefits of PAP among patients. Corrigan et al. (2022) was the only article to explore predictors of appeal with favourable attitudes toward psychedelics associated with having a diagnosis that was indicated for PAP, previous psychedelic use, being younger, employed, and having no religious affiliation. Such participants were more likely to accept psilocybin if recommended by their doctor and to come off medication to do so. Additionally, males had a higher lifetime use and psychedelic knowledge than females. However, no association was found between education level and beliefs.
Harding et al. (2021) consulted patients with eating disorders and found they were overall ambivalent towards existing pharmacological and psychological treatments. While many were satisfied with their current treatment, especially psychological therapy, a significant portion had considered novel treatments such as PAP, in part due to the significant impact of living with their diagnosis. Jilka et al. (2019) consulted people diagnosed with depression and found their experiences with antidepressant medications to sometimes be a long, uncertain process. For these participants, ketamine's rapid effect contributed to its appeal. Broadly, participants accepted ketamine to be effective in managing depression, despite noting gaps in current research. In another study, 30% of mental health service users agreed that psilocybin could be helpful for their mental health problems (Corrigan et al., 2022). Finally, most fibromyalgia patients surveyed by Glynos, Pierce, et al (2022) believed psychedelics could treat chronic pain and would be willing to participate in a clinical trial exploring efficacy.
Barriers and concerns
Six articles exploring patients' attitudes reported barriers to accessing PAP, with concerns about funding, regulations, and stigma being prominent themes. Of mental health service users in Corrigan et al. (2022), 52% agreed that the government should fund psilocybin studies. The cost of accessing the drug itself was a concern for patients when discussing the therapeutic use of ketamine for depression (Jilka et al., 2019, 2021), with patients suggesting that clinicians might be hesitant to prescribe due to a lack of NHS funding and high prices from pharmaceutical companies (Jilka et al., 2021). Concerningly, another group of patients was willing to buy ketamine off the street if it was cheaper than an NHS prescription (Jilka et al., 2019). Among fibromyalgia patients, 36% of the psychedelic naïve participants noted the legal status of psychedelics as one of the reasons they would not want to participate in a clinical trial (Glynos, Pierce, et al., 2022).
Patients also discussed regulations they would like to see if PAT was to be effectively implemented. Some patients felt a need to address the reputation of ketamine as an addictive party drug (Jilka et al., 2019, 2021), suggesting this could be achieved via public education campaigns and regulations (Jilka et al., 2021). However, concerns about stigma were not universal; almost half of one sample of patients with eating disorders stated they had no concerns about stigma. Patients with depression were divided on the appropriate location for ketamine administration, with equal portions supporting and opposing clinic-based administration (Jilka et al., 2019). Most agreed that psychiatrists should be able to prescribe the drugs and were open to shifting the responsibility to a trained GP after initial monitoring to ensure side effects, costs, and qualifying criteria are appropriately managed.
Six of the patient-focused articles included commentary about side effects (Corrigan et al., 2022; Glynos, Pierce, et al., 2022; Harding et al., 2021; Jilka et al., 2019, 2021; Spriggs et al., 2021). A minority of participants expressed concerns, with these being a rationale for their unwillingness to try PAP (Corrigan et al., 2022; Glynos, Pierce, et al., 2022; Harding et al., 2021). However, in other studies, participants were willing to risk side effects if treatments might improve their depressive symptoms (Jilka et al., 2019, 2021). Another study reported that participants found the concept of a full psychedelic experience intimidating, citing a reluctance to give up control, but noted possible solutions to overcome this discomfort (e.g., adequate information/preparation, trust with guides) (Spriggs et al., 2021).
Public
Six of the 29 articles reported on public perceptions of PAP. The public samples were diverse and included parents, college students, nightclub attendees, psychedelic conference participants, and those involved in psychedelic online forums.
Knowledge
Most articles examining public perceptions of PAP addressed some aspect of knowledge. The Croatian general public's objectively assessed knowledge of psychedelics was moderate (median score 64/100) (Žuljević et al., 2022). US college students self-reported their knowledge, with half agreeing/strongly agreeing they were “knowledgeable about hallucinogenic drugs”. However, 74% of the sample were unaware of current research into hallucinogenic research (Wildberger et al., 2017). Naturalistic users of psychedelics demonstrated relatively good objective knowledge, being generally aware of recent clinical trials, with most correctly identifying target disorders for which efficacy has been established (Kruger, Glynos, Fields, Herberholz, & Boehnke, 2022). About two-thirds of this sample also demonstrated a good understanding of current psychedelics regulations and therapeutic approaches to PAP. One-third of UK nightclub attendees were aware of the recent approval of esketamine for treating depression (Grabski, Waldron, Freeman, van Laar, & Curran, 2022). Finally, among psychedelic activism event attendees, 21% perceived healthcare providers to have poor knowledge of psychedelics and PAP (Glynos, Fields, et al., 2022).
Appeal and benefits
Five articles explored the perceived appeal and benefits of PAP among the public. The majority of US college students had neutral opinions about the therapeutic use of psychedelics, with only 33% indicating support (Wildberger et al., 2017). Among the Croatian general public, those who were younger, male, and had a lower educational status, expressed more positive attitudes towards PAP (Žuljević et al., 2022). Among nightclub attendees in the UK, those who were aware of the recent approval of esketamine compared to those unaware reported greater endorsement of ketamine as a safe and effective treatment for depression (Grabski et al., 2022). In a survey of naturalistic psychedelic users, 71% stated they would be highly likely to accept PAP by a trained therapist if it were legal (Glynos, Fields, et al., 2022). A survey of parents exploring attitudes towards ketamine treatment for adolescent mood disorders, reported high acceptability of ketamine use, albeit with significantly higher acceptability ratings for use with suicidality than bipolar or MDD (Mathai et al., 2021). Individuals with a bachelor's degree (or higher) and those with a self-reported family history of mood disorders had significantly higher acceptability ratings, whereas, income did not affect ratings. Greater familiarity with other treatments, personal experience, satisfaction with antidepressants, and comfort with their children using psychiatric medication were all associated with higher acceptability.
Barriers and concerns
Common barriers and concerns included perceived risks, side effects, and problems with PAP administration. In a sample of US college students, the majority supported further psychedelic research and thought this should be federally funded (Wildberger et al., 2017). Regarding safety, a majority of the students believed that psychedelics are ‘unhealthy’ and addictive, with an equal proportion agreeing and disagreeing that hallucinogenic drugs could be safely enjoyed recreationally. Among nightclub attendees, those unaware of the recent esketamine policy change had higher risk perceptions of medicinal ketamine than those who were aware. The risk associated with recreational ketamine use was rated equally high between these two groups, suggesting that the policy change impacted risk perceptions of medicinal use but not recreational use (Grabski et al., 2022). Among naturalistic psychedelic users, participants reported stigma (56%), privacy (41%), and legality (38%) as reasons not to speak to their primary healthcare provider (PCP) about psychedelic use (Glynos, Fields, et al., 2022). Those who had spoken with their PCP about psychedelics were more likely to be older, have greater lifetime usage, and were more willing to engage in PAP with a trained guide, with 52% stating they felt very comfortable when speaking to their PCP about their psychedelic use. Parents primary concern about ketamine being prescribed to adolescents with mood disorders included potential side effects and lack of FDA approval, with less frequently reported concerns including abuse potential, age of the child, and the child's own treatment decision-making capacity (Mathai et al., 2021). Concerns about side effects varied depending on the diagnosis/application, with the proportion reporting concern being greatest for MDD, less for bipolar, and less again for suicidality. Furthermore, there appeared to be less hesitation and more willingness if the treatment was shorter and less invasive, with participants showing a preference for nasal spray administration, followed by oral/sublingual, intravenous infusion, and intramuscular injection.
Reporting biases
All articles included in this review were of moderate to high quality. Across the stakeholder groups, research focused on patient populations had the highest quality rating (91%), followed by health professionals (86%), and then finally public (85%). Using the QuADS criteria, the most common limitations were poorly outlined rationale or consideration of sample size requirements and limited evidence of stakeholder consultation regarding research design or processes. Some articles also included a limited rationale for the choice of data collection tools and incomplete reporting of recruitment data. On average, quantitative studies had lower quality ratings (81%) than both mixed methods (91%) and qualitative research (91%).
Discussion
This review explored knowledge, perceived appeal or benefits, and barriers or concerns among three key stakeholder groups; health professionals, patients, and the public. Despite these three groups having different perspectives and priorities, several similarities were observed, including generally low knowledge about PAP and shared support of continued research. Below, findings are discussed in relation to relevant literature in other contexts, and future research directions are considered.
The finding that knowledge (primarily self-reported) was generally low across all groups is consistent with other emerging treatment modalities (Stern et al., 2016). In health professionals, being a trainee predicted higher knowledge, likely resulting from evolving clinical training curricula (Page, Rehman, et al., 2021). Exposure to recent research appears to shift opinion, with one study reporting that participants expressed “cautious curiosity” and increased positive perceptions following an information session (Reynolds et al., 2021). It is common practice for naturalistic users to seek information about psychedelics (Kruger, Enghoff, Herberholz, Barron, & Boehnke, 2023). Among the reviewed studies, previous use of psychedelics consistently predicted greater awareness, interest, and knowledge. Patients and public both perceive health professionals to have low or limited knowledge of PAP, which appears to reflect health professionals' own opinions outlined in this review. Some research suggests that naturalistic users rarely defer to health professionals as a trusted source of knowledge (Kruger et al., 2023), as evidenced by reported fears of stigma and judgment. Removing barriers for patients to approach health professionals about psychedelic use should be a priority, moving away from abstinence-based approaches towards more compassionate and destigmatizing acceptance of patient autonomy (Gorman, Nielson, Molinar, Cassidy, & Sabbagh, 2021). Of note, only three of the reviewed papers assessed knowledge objectively (Barnett et al., 2022; Kruger et al., 2022; Žuljević et al., 2022), and the remaining 26 assessed self-reported knowledge. Due to the subjective nature of these ratings', knowledge-based findings should be interpreted with caution (Tracey et al., 1998). It would be beneficial for future research to utilise more objective measures of knowledge; this will allow a better understanding of current gaps and target areas for education and training purposes.
Most participants expressed favourable views towards PAP, especially those younger, male, or with greater psychedelic knowledge or experience. Our finding that lack of religious affiliation predicted more favourable attitudes in patients reflects previously established links between religion and perceived immorality of drug use (Stylianou, 2004). Greater familiarity with other treatment modalities, including those considered more ‘extreme’ or invasive, such as pharmacological interventions or electroconvulsive therapy, appeared to make PAP more attractive. Similarly, the more severe the target disorder, the more likely parents in this sample were to be accepting of a psychedelic (ketamine) as a treatment (i.e., suicidality vs mild depression), suggesting varying risk tolerance and matching treatment decision processes outlined in previous research (Gaudiano, Ellenberg, Schofield, & Rifkin, 2016; Rajendran et al., 2012; Rodenburg-Vandenbussche et al., 2018).
PAP was noted as novel and exciting among health professionals and patient populations. There appeared to be a high degree of willingness to try these treatments among patients and the public, with the recognition that there was still uncertainty surrounding potential risks and efficacy. Official statements from the American Psychiatric Association highlight these uncertainties, expressing concerns that the combination of public and commercial interests and the need for efficacious treatments for challenging conditions will lead to psychedelic usage outpacing evidence-based research (Knopf, 2022). This hesitation and lack of endorsement likely explain why many in the psychiatric profession were unlikely to report full support for PAP.
All three groups commented on the legal status of psychedelics as a barrier to access. Health professionals' criticisms of current scheduling mirrors evidence asserting that drug policy does not accurately reflect the real risks or harms posed by psychedelics (Nutt, King, & Phillips, 2010) and perpetuates the stigma associated with PAP (Nutt et al., 2013). This review provides some initial evidence to refute concerns about the role media coverage and shifting drug policy may have in reducing risk perceptions of recreational usage (Government, 2022; Grabski et al., 2022). Awareness of the recent approval of esketamine for depression in the UK led to lower risk perceptions of therapeutic but not recreational usage, suggesting that the public can distinguish between these two applications. However, as approvals lag in some places and move forward in others, increases in underground therapy and black-market drug use may still increase (Andersson, Persson, & Kjellgren, 2017; Inserra, 2019; Jade, 2018, pp. 1–6), suggesting a need for improvements in education, regulations, and more precise differentiation between recreational and therapeutic applications.
The potential side effects or risks of PAP were reported as a concern across all groups. However, some patients engaged in a form of risk-benefit analysis common in treatment decision-making (Wouters et al., 2014), indicating a willingness to try such treatments if they had promise while also acknowledging potential risks. Health professionals reported concerns about psychiatric and neurocognitive risks, highlighting the need to consider the vulnerabilities of certain populations and any contraindications. Several questions or concerns surrounding implementation were noted, with strong, consistent themes among the three groups. The eventual cost of treatment was perceived as a possible barrier to access, and participants reported uncertainty about who, how, and where PAP would be delivered. PAP has different time, logistical, and ethical characteristics compared to other treatment modalities, with these issues needing clarification before treatment adoption (Belouin et al., 2022).
Nearly all research included in this review was impacted by self-selection bias and limited diversity. Although some studies utilized random sampling, low response rates mean the resultant samples may not have been representative of the broader populations. Those who agreed to participate in these studies may have had more polarised views, or more familiarity with psychedelics, inherently limiting the generalisability of this work. Furthermore, low diversity was a consistent limitation. Low cultural and ethnic diversity is commonly reported across psychedelic studies (Michaels, Purdon, Collins, & Williams, 2018), which not only does a disservice to the rich indigenous history of psychedelics but limits the appropriate development of PAP to meet the needs of indigenous, minority ethnic, and cultural groups. Research exploring the perspectives of these groups is of immense importance to help guide the direction and development of psychedelic interventions. Of the included studies, only four included commentary on the indigenous history of psychedelics and the role modern research could play in amplifying these voices (Beaussant et al., 2020, 2021; Reynolds et al., 2021, 2022). Participants in these studies also commented on the potential limitations of the medical model to fully capture and comprehend the psychedelic experience (Beaussant et al., 2021; Reynolds et al., 2021), further highlighting the integral role that traditional knowledge or non-western models of well-being can have in psychedelic research.
Strengths and limitations
This review explores the perspectives of three key stakeholder groups relevant to PAP. The development of psychedelic research is dependent on the views of these groups in unique ways; professionals may have a direct hand in the design of research, patient perspectives impact uptake and participation, and the public contribute to the broader social narrative surrounding psychedelics and psychedelic interventions. All three groups may also impact governmental or legislative action in this area.
Although this review aimed to define explicit inclusion and exclusion criteria, discrepancies in definitions and terminology led to a re-evaluation of the criteria after the initial search had been conducted. Furthermore, not all of the included studies addressed each of the objectives. Although the likelihood of this occurring was outlined a priori, it limited our ability to make inferences between the frequency of an outcome and its relative importance among stakeholder groups. Additionally, our definition of ‘public’ created a somewhat disparate group, defined by what they were not rather than what they were, i.e., those not providing or receiving treatment.
Conclusions
As interest in psychedelics and their therapeutic potential grow, health professionals need to be educated on the evidence base regarding their therapeutic use. It is vital that patients feel comfortable discussing psychedelics with their health professionals and that, in turn, providers be knowledgeable in their responses. Well-informed health professionals may mitigate risks associated with self-experimentation or seeking underground access to psychedelics (Andersson et al., 2017; Jade, 2018, pp. 1–6). Furthermore, there needs to be clarification on how PAP training is delivered, who may be eligible to receive this training, and what type of regulations or oversight may be necessary (Belouin et al., 2022; Gorman et al., 2021) and training programs must provide guidance on the ethical challenges associated with working with people experiencing altered states of consciousness.
Future research should also consider how people acquire knowledge, the types of sources they are exposed to, and their impact on perceptions. Most people have been exposed to media messages and hype regarding PAP. This effect has been termed ‘dark loops,’ and further research is necessary, both to develop accurate methods of measuring the effect and to consider the impact of different methods of management (Noorani, Bedi, & Muthukumaraswamy, 2022). Finally, as discussed earlier, the lack of diversity across all areas of psychedelic science should be of great importance to researchers in this field.
Acknowledgements
The author AW was supported by a University of Auckland Doctoral Scholarship, and the author MF was supported by a University of Auckland Summer Research Scholarship.
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Appendix 1: Summary of included studies
| Reference | Country | Aim of study | Participants (type) | Sample size | Study design | Methodology | Outcomes | Key findings |
| Barnett et al. (2022) | USA | To explore psychiatrists' opinions on the therapeutic use of psychedelics | Health Professionals. Psychiatrists | 104 | Cross-sectional survey, quant | Psychiatrists attending PAP presentations at two conferences, recruited before entry to complete an anonymous survey. | Survey assessed participants' psychedelic knowledge, opinions, concerns around legalisation, educational interests, and sources of information. | Participants had favourable attitudes towards psychedelic treatments, and supported legalisation for medicinal use. Perceived barriers included, lack of training and education. Concerns included complicated administration factors like time demands, logistics and use with patients with contraindications. |
| Barnett et al. (2018) | USA | To explore American psychiatrists' attitudes towards classic hallucinogens | Health Professionals. Resident-fellows, attending psychiatrists | 324 | Cross-sectional survey, quant | Randomly selected members of the American Psychological Association were emailed an online anonymous survey. | Opinions on the potential and risks of hallucinogenic use. Attitudes towards medical supervision, legal and research status. | Hallucinogens were viewed as potentially risky, with possible psychiatric and cognitive complications. Support for restrictions on recreational use and further research into therapeutic potential. Large minority optimistic about use of psychedelics for psychiatric treatment. |
| Beaussant et al. (2020) | USA | To explore expert views on psychedelic assisted therapy with patients with serious illness. | Health Professionals. Experts in serious illness care and/or psychedelic research | 17 | Cross sectional, qualitative semi structured interview | Semi-structured interviews conducted in person or via video. | Concerns, potential, research priorities, and delivery associated with PAP. | Mixed view, both support for potential and concern about vulnerable population. Prioritise research for people with psychiatric distress. Need for safety and efficacy guidelines to guide integration into existing models of care. |
| Beaussant et al. (2021) | USA | To outline the research agenda on the use of psychedelic assisted therapies with people with serious illness | Health Professionals. Targeting experts in treating those with serious illnesses. | 19 | Focus groups, qual | Two-day seminar, small and large focus groups. Preconference interviews guided seminar agenda. | Four key areas, perspectives on historical context, existing research, current priorities, and outlining future directions (possible issues and fostering collaboration). | Seven key areas, four in the science and design of PAP (indications, therapeutic protocols, set/setting, mechanism of action) and three pertaining to institutional and societal drivers (education/certification, regulation/funding, diversity/inclusion). |
| Brennan et al. (2021) | USA | To understand the unique relational challenges faced by psychedelic practitioners and the practices they utilise to cope with this | Health Professionals. Practitioners with experience administering MDMA/psilocybin in underground settings | 23 | Cross sectional, Semi-structured interview, qual | Participants completed a one-on-one anonymous phone interview. Transcripts underwent thematic analysis | Interested in the ethical barriers and challenges presented by psychedelic healing work. Ethical practices to navigate these were noted. | Participants identified unique ethical challenges associated with PAP (nudity, touch, therapist use of psychedelics, transference, supervision, scope of competence) and practice solutions (personal therapeutic work, supervision/consultation and attentiveness). |
| Callon et al. (2021) | Canada | Gain insight from ayahuasca ceremony leaders to improve outcomes and minimize risk associated with ayahuasca use | Health Professionals. Ayahuasca ceremony leaders | 15 | Semi-structured interview, qual | 90-min semi-structured phone interview, qualitative content analysis. | Specific preparation and integration practices were of key interest | Participants reported on safe an effective preparatory and integration practices, noting a need to develop evidence-based practices utilised by all practitioners, engage in quality training, and consider implementation characteristics. |
| Corrigan et al. (2022) | Ireland | Understand mental health service users' perceptions of psilocybin therapy and psychedelics | Patients. Mental health service users | 99 | Cross sectional quantitative survey | Participants recruited from a community mental health services and a hospital. Completed survey. | Acceptability, concerns and attitudes towards safety were of interest. Diagnosis, age, previous experience and religion were also analysed. | A majority of participants agreed that psilocybin should be granted medical status and approved of further research into its medicinal value. Those who were younger, had psychedelic experience, and were non-religious had more favourable attitudes towards PAP. |
| Davis et al. (2022) | USA | Explore psychologists' attitudes and beliefs about psychedelics and the use of psilocybin therapy | Health Professionals. Psychologists | 366 | Cross sectional, quasi-experimental survey, quant | Recruitment via email database of psychologists in the US. Completed an electronic survey. | Assessed attitudes towards psychedelics, vignettes comparing PAP to other treatments for multiple disorders. | Participants tended to hold favourable attitudes towards general psychedelic experiences but maintained caution and concern around the psychiatric and cognitive risks of psilocybin therapy. Participants lacked necessary knowledge to recommend treatment. |
| Earleywine et al. (2022) | USA | To define integration therapy and understand perspectives and concerns of therapists | Health Professionals. Integration therapists | 30 | Cross sectional, Semi-structured interviews, mixed method | Semi-structured interviews underwent thematic analysis. Quantitative analysis was used to understand the varying presence of themes. | To highlight recurring themes in participants definitions of integration. Note challenges across personal practice and the field as a whole | Integration was summarised as a bridge across the psychedelic experience to everyday life. Challenges in therapy mentioned were a lack of client engagement or resistance and the need for self-care for the therapists. General concerns included commercialisation of PAP, unrealistic expectations, power imbalance, and the importance of collaboration between service providers. |
| Glynos, Fields, et al. (2022) | USA | Understand naturalistic psychedelic use and its relationship to healthcare | Public. Attendees of a psychedelic activism event, users of psychedelic social media forums. | 1,435 | Cross sectional, survey, quant | Participants recruited in-person at a psychedelic activism event and online, to complete an anonymous online survey. | Key questions revolved around the disclosure of psychedelic use to participants healthcare providers. Outcomes of personal psychedelic self-medication was also investigated. | Most participants did not discuss or disclose psychedelic use with their health care provider. Main concerns identified included stigma, legal barriers, and a perceived lack of knowledgeable health care providers. There was interest in legal access to PAP. |
| Glynos, Pierce, Davis, McAfee, and Boehnke (2022) | USA, Canada | To investigate attitudes, uses and perceptions of psychedelics among people with Fibromyalgia. | Patients. People with Fibromyalgia, experienced and non | 354 | Cross sectional, quantitative survey. | Participants recruited via e-mail and social media sites, to complete an online anonymous survey. | To understand the Interested in motivations and barriers to psychedelic use. Investigating the relationship between psychedelic use and pain symptoms and wellbeing. | Participants noted interest in psychedelic research and its potential for pain management- reporting willingness to engage in clinical trials. |
| Grabski et al. (2022) | UK | To evaluate perceptions around recreational ketamine use, in light of esketamine being approved to treat depression | Public. Nightclub attendees, frequent EDM festival attendees. | 2,415 | Longitudinal survey, quantitative | A part of the online Electronic Music Scene Survey, tracking drug use in five European countries (Time points: 2017, 2018, 2020) | Attitudes towards, usage, and risk perceptions of ketamine use (recreational and medical antidepressant), in context of esketamine policy. | No association found between the approval of medical esketamine and participants risk perception of recreational ketamine. No association with increased use either. |
| Harding et al. (2021) | UK | To understand how people with eating disorders currently perceive psychedelic treatment and research | Patients. Eating disorders | 200 | Cross sectional, survey, mixed methods | Participants with a self-reported diagnosis of eat disorder were recruited via social media to participate in an online survey. | Beliefs and concerns of participants towards psychedelic treatment options, current use of complementary/alternative treatment modalities. | Approximately half indicated willingness to engage in psychedelic research. A moderate level of concern was reported, with participants suggesting means to reduce this concern. including, health professional education and endorsement, a safe environment, and good rapport. |
| Hearn et al. (2022) | USA | To investigate counsellors attitudes towards psychedelic assisted therapy and psychedelics | Health Professionals. Counsellors, students, counsellor educators | 223 | Cross sectional survey, quant | Counsellors were recruitment via email (list provided by licensing boards), and CESNET to complete an online survey. | Perception of PAP and attitudes towards personal psychedelic use to facilitate PAP training. | Mixed views on psychedelic use and PAP. Participants saw the potential of PAP with medical supervision and endorsed a need for further research. |
| Jilka et al. (2019) | UK | To explore patients' and carers' perceptions of ketamine treatment. | Patient. People with depression or addiction and their carers' | 44 | Cross sectional, mixed methods, focus groups and quantitative survey | Participants recruited from various service user groups or organisations to participate in focus groups, with a survey component. | Discussions centred around participants opinions on how ketamine should be utilised, and their priorities on how it could be prescribed and supervised. | Ten themes were generated monitoring, information, effect on daily life, side-effects, recreational use, effectiveness, appropriate support, cost, stigma and therapy. Participants called for further evidence of safety, and identified access issues (travel to clinics and uninformed medical staff). |
| Jilka et al. (2021) | UK | To explore the views of people with depression who had no experience with ketamine use. To seek recommendations on the clinical use of ketamine | Patients. People with depression. | 14 | Focus group, qualitative | Participants with a diagnosis of depression were recruited via a local hospital, previous research list, and local service-user advisory groups, to participate in 3 focus-groups and 3 member-checking sessions. | Assess opinions on the clinical use, administration and monitoring of ketamine treatments | Five themes were generated, changing public perceptions, risks, monitoring, privacy and data protection, and practical aspects. Participants were aware of public stigma associated with ketamine as a recreational drug, calling for better education, and evidence of safety. Aspects of treatment duration, administration, and accessibility were considered. |
| Kruger et al. (2022) | USA | To assess the psychedelic knowledge of people who use psychedelics naturalistically | Public. Naturalistic users. | 1,435 | Cross sectional, survey, quant | Participants recruited in-person at a psychedelic advocacy event and online via social media. | To assess psychedelic knowledge such as classifications, legal status, efficacy, side effects. | Participants tended to have “substantial” knowledge – with many correctly answering questions about legal status, clinic trials and side effects. Participants tended to overestimate the therapeutic potential of psychedelics. |
| Levin et al. (2022) | USA | To investigate how psychiatrists' perceptions of psychoactive drugs compare to risks outlined in US drug policy | Health Professionals. Psychiatrists | 181 | Cross sectional, quasi-experimental survey, mixed method | National convenience sample of psychiatrists, recruited via email (purchased from a marketing company). | To understand how psychiatrists rate the safety, abuse potential and therapeutic potential of “non-prescribed controlled substances” AND how they align with US controlled substance act schedule. | Found participants perceptions of safety and potential of these drugs did not align with current drug policy. Use of non-prescribed methamphetamine was perceived as more concerning than use of non-prescribed psilocybin or ketamine. |
| Luoma et al. (2022) | USA | Investigate predicting factors of psychologist's attitudes towards psychedelics | Health Professionals. Clinical or Counselling Psychologists | 366 | Cross sectional, survey, quant | Participant recruited via a purchased email database, to participate in an online survey. | Perceptions of using psychedelic substances in psychotherapy, predictors of varied attitudes. | Those who were male, younger, had more extensive knowledge of psychedelics, had no religious affiliation, personal experience or knowing someone with, and education was associated with more positive attitudes. |
| Mathai et al. (2021) | USA | Assess parent's attitudes towards ketamine treatment for adolescent mood disorders and suicidality | Public. Parents | 283 | Cross sectional, survey, quant | Participants recruited through Amazon Mechanical Turk to complete an online survey. | Investigating parents trust, preferences and concerns for the therapeutic use of ketamine | Participants displayed high acceptability levels for the therapeutic use of ketamine for suicidality and mood disorders in adolescents. Concerns related to side effects and lack to regulation/government approval. |
| Mayer et al. (2022) | USA | Investigate palliative care providers perceptions of psilocybin therapy for existential distress. | Health Professionals. Palliative Care Providers (physician, nurse, chaplain, pharmacist) | 5 | Cross sectional, semi-structured interview, qual | Purposeful sampling of an academic medical centre palliative care team, to participate in a 45-min Zoom semi-structured interview. | To explore perspectives on psilocybin therapy and to gain understanding of experiences working with those with existential distress. | Four themes were identified. Multi-level barriers to exploring and addressing existential distress, the duality and power of presence, suffering as an intrinsically subjective phenomenon, and uncertainty about the risks and benefits of psilocybin. |
| Meyer et al. (2022) | USA | Explore mental health professionals attitudes towards psilocybin | Health Professionals. Mental health professionals | 155 | Cross sectional, survey, quant | Participants recruited via email to participate in an online survey. | Attitudes, knowledge and beliefs. Compared effects of terminology “psilocybin” or “magic mushrooms.” | Neutral attitudes, with low self-reported knowledge. Gender, attitudes towards medicinal cannabis, psychedelic use influenced attitudes. No impact of terminology. |
| Page et al. (2021a,b) | UK | Explore psychiatrists existing knowledge and attitudes towards psychedelic assisted psychotherapy | Health Professionals. Psychiatrists at an NHS mental health trust | 83 | Cross sectional, survey; focus group, mixed method | Email recruitment within one NHS mental health trust to participate in an online survey, with an invitation to attend a focus group. | Explore potential barriers and recommendations for the implementation of PAP | Participants tended to hold positive views about the potential for such therapy. Study concluded they were not confident or trained enough to implement such treatments. A need for professional and societal shifts was noted. |
| Reynolds et al. (2021) | New Zealand | Investigate cancer healthcare professionals' perceptions of psychedelic-assisted therapy | Health Professionals. Advanced cancer healthcare workers/supports (doctors, nurses, psychologists, social workers) | 12 | Cross sectional, semi-structured interview, qual | Participants recruited via email to cancer services and flyers presented at clinical meetings, to participate in a semi-structured interview, thematic analysis. | To assess awareness, knowledge and perceptions of the treatment use with people with advance cancer. Specifically, those who have depression and/or anxiety. | Openness to PAT was generally displayed, linked to the need for effective, transformative treatment. Acceptability was shaped by the need for extensive research and ensuring safety. |
| Reynolds et al. (2022) | New Zealand, USA | To investigate cancer healthcare professionals from the US and NZ perceptions of psychedelic assisted therapy | Health Professionals. Cancer healthcare practitioners | 245 | Cross sectional, survey, quant | Convenience sampling via medical networks, and social media advertisements, to participant in an anonymous online survey. | Perceptions of psychedelic assisted therapy and trials, identify predictive variable, and make comparisons between US and NZ samples. | Positive views of PAT potential with cancer patients, support for further research, importance of considering spiritual and indigenous perspectives. USA greater awareness, NZ greater perceived importance of spiritual/indigenous perspectives. |
| Spriggs et al. (2021) | UK | Gather AN patients perceptions towards psilocybin-assisted therapy and research | Patients. Anorexia nervosa | 11 | Cross sectional, Focus groups, qual | Recruited via social media advertisements to participate in an 2-h online focus group. | To investigate what barriers are present in AN treatment Defining “recovery” as according to patients. | Participants noted the lack of control over experiences in PAT was of concern. Education, communication and good rapport was a possible solution. |
| Wildberger et al. (2017) | USA | Investigate college students' perceptions of medicinal value of hallucinogens | Public. College students | 124 | Cross-sectional survey, quantitative | Randomly recruited in two college campuses to complete a survey. | Assessed potential benefits, negative effects, and self-reported knowledge of hallucinogenic drugs. | Participants reluctant to agree that substances had therapeutic value, but supported further research into potential benefits. |
| Winkler and Csémy (2014) | Czech Republic | To follow up with mental health professionals who previously experimented with LSD | Health Professionals. Mental Health professionals | 22 | Structured interviews, qualitative | Contacted authors (who had self-experimented) of LSD research (1952–1974) to participate in a structured interview. | To assess attitudes towards the potential use of LSD in the mental health area. | The potential benefits of LSD were supported for “didactic and auto-gnostic purposes”. |
| Žuljević et al. (2022) | Croatia | To develop and test a questionnaire that captures attitudes towards psychedelics | General public. | 1,153 | Cross sectional, survey, quantitative. | Convenience, snowballing sample of general public, using online advertisement, to complete an online survey. | To assess its reliability and validity To assess the tests scores relationship to psychedelic knowledge scores | Psychedelic knowledge was associated with attitudes. Those who were male, younger, or had lower education status, expressed more favourable views. |
