Abstract
Interest in psychedelic research in the West is surging, however, clinical trials have almost exclusively studied synthetic compounds such as MDMA, ketamine, DMT, LSD, ibogaine, and psilocybin. To date, few clinical trials have utilized whole mushroom/plant material like Psilocybe mushrooms, Iboga, or Ayahuasca. Individuals participating in the Roots To Thrive Psilocybin-Assisted Therapy for End of Life Distress program were administered synthetic psilocybin, whole Psilocybe cubensis, and mycological extract on separate occasions and post-treatment interview transcripts were qualitatively analyzed to discern themes and patterns. There was broad consensus that all three forms were helpful and similar, all generating visual and perceptual distortions, emotional and cognitive insight, and mystical experiences. However, synthetic psilocybin was said to feel less natural compared to organic forms, and the overall quality of experience of synthetic psilocybin was inferior to the organic forms. Research should be conducted with whole psychedelic mushrooms and extract in addition to synthetic psilocybin given this preliminary data, especially when considering that medicine keepers around the world have utilized whole mushrooms and plant material for millennia.
Introduction
Background
Psychedelic pharmacology is currently being researched as a new frontier in psychiatric medicine. In particular, a diverse range of compounds, namely psilocybin, MDMA, DMT, LSD, and ketamine, are being explored for their ability to alleviate mental health conditions when combined with psychotherapy and administered in controlled clinical settings (Andersen, Carhart-Harris, Nutt, & Erritzoe, 2021; Davis et al., 2021; Drozdz et al., 2022; Gasser et al., 2014; Mitchell et al., 2023). To date, most psychedelic compounds that have been studied in clinical trials in the West have been synthetically derived (Ali, Gifford, Lowe, Gordon, & Grant, 2023; Ching et al., 2024; Goodwin et al., 2022), while this is not the case in other parts of the world (Cavanna et al., 2022; Osório et al., 2015). Amongst some Indigenous societies around the world, psychedelic plants such as San Pedro (Echinopsis pachanoi), brews such as Ayahuasca (containing the plants Psychotria viridis and Banisteriopsis caapi), and fungi like Psilocybe mushrooms, are ingested in their natural form (Apud, 2015; Carod-Artal & Vázquez-Cabrera, 2006; Guzmán, 2008).
Clinical trials form the bedrock for medical science in the Western world. They intend to gather important data about the safety, tolerability, and efficacy of drugs like psychedelics (Andersen et al., 2021). However, while they offer insightful empirical data, clinical trials are limited in a number of ways. For one, they require utilizing precise and standardized doses of active compounds, and the variability of alkaloids within whole organic plants or fungus-like Psilocybe fungi make this impossible (Van Court et al., 2022). Thus, studying whole plants and fungi may be seen as incompatible with the traditional clinical trial study design. Another barrier to researching whole psychedelic plants and fungi is that they are difficult to patent (Ghijsen, 2009; Wong & Chan, 2014), making interest in them secondary to those with primary interests in profit and commercial viability. It has been argued that this makes funding for psychedelic plants and fungi significantly harder to secure (Hall, 2021). These factors have led to a lack of clinical trials examining the effects of whole psychedelic plants on mental health conditions like PTSD, depression, and anxiety (Escamilla et al., 2023).
There is evidence to suggest why whole psychedelic plants and fungi may deliver a different effect than synthetic compounds currently being lionized in the field. In particular, preliminary findings point to some subjective effects caused by Psilocybe cubensis and synthetic psilocybin differ in some ways and are similar in others (Ona & Bouso, 2021; Ribeiro, 2018). In a review, Ali et al. (2023) identified numerous additional compounds that naturally occur in psilocybin-containing fungi, which may enhance therapeutic effects.
Synthetic psilocybin
Psilocybin was first synthesized by Dr. Albert Hofmann in 1958 upon being introduced to Psilocybe mexicana by pediatrician and mycologist, Dr. Valentina Wasson and her husband R. Gordon, who obtained the fungus from traditional Mazatec healer, Maria Sabina (Sharma et al., 2023; Tylš, Páleníček, & Horáček, 2014; Williams, Bartlett, Michaels, Sevelius, & George, 2020). Since then, numerous other synthesis techniques have been developed (Gibbons, McKinney, O'Dell, Bollinger, & Jones, 2021; Shirota, Hakamata, & Goda, 2003). Some have also synthesized other psychedelic alkaloids found within Psilocybe species such as baeocystin, norbaeocystin, norpsilocin, and aeruginascin, which may have notable psychoactive properties (Sherwood et al., 2020a, 2020b). A survey of the United States Patent and Trademark Office (USPTO) database reveals a multitude of patents related to analogues of psilocybin and psilocin.
Psilocybin-containing fungi
Mushrooms containing psilocybin have existed for more than 60 million years (Bradshaw, 2024). It is not known why fungi produce psilocybin, however, there may be an evolutionary advantage to its production. Psilocybin is the prodrug of its active form, psilocin, which is converted by stomach enzymes once ingested (Dinis-Oliveira, 2017). It can be located in a variety of species including those found in the genera Psilocybe, Panaeolus, Gymnopilus, Inocybe, Pluteus, Pholiotina, and Galerina (Stamets, 1996) (Table 1).
Mushroom Genera Containing Psilocybin species*
| Genus | Species No. | Psilocybin concentration |
| Psilocybe | 162 | <4% |
| Panaeolus | 20 | <4% |
| Gymnopilus | 12 | <2% |
| Inocybe | 6+ | <2% |
| Pholiotina | 4 | <1% |
| Pluteus | 2 | <1% |
| Galerina | 1 | <1% |
| Massospora | 1 | <1% |
*Note. More species are being discovered whilst some species are now known to be synonyms, hence these numbers are in a constant state of flux.
Mushroom chemical makeup
While primary interest in Psilocybe and similarly psychoactive mushrooms revolves around the actions attributed to psilocybin, or more specifically psilocin, psilocybin-generating mushrooms also contain a range of other various alkaloids with some demonstrating properties such as baeocystin, norbaeocystin, serotonin, tryptophan and phenylethylamine (Reinert, Colunga, Etuk, Richardson, & Dunn, 2020). This makes it unlikely that consuming psilocybin or psilocin alone would be phenomenologically or pharmacologically identical to consuming similar amounts of the entire mushroom (Wieczorek et al., 2015). Other non-psychoactive compounds present in diverse psychedelic fungi include vitamins that may impact one's psychedelic experience by reducing the possibility of migraine, and preventing hydration (Schindler et al., 2021). Niacin in the form of nicotinamide or niacinamide is also a notable B vitamin co-occurring compound in many species related to and presumably found also in Psilocybe mushrooms, which could enhance carrying other alkaloids from the mushroom such as psilocin throughout the body. The presence of phenylethylamine in select psychedelic mushrooms can also intensify the effects of psilocin (Reinert et al., 2020). The compound aeruginascin, found in some psychedelic mushrooms from the genus Inocybe, has been associated with increased feelings of euphoria during the dosing experience (Gartz, 1989) while ß-carbolines found in Psilocybe mushrooms appear to interfere with the breakdown of psilocybin in the body (Blei et al., 2020).
Ultimately, the presence of myriad co-occurring chemicals within psychedelic mushrooms likely catalyzes synergistic effects in ways similar to the complex chemical interactions observed with cannabis and ayahuasca pharmacology (Barnes, 2006; Oreja-Guevara, 2012). Thus there is clinical rationale for hypothesizing that whole mushrooms may produce a different experience in the context of psychedelic-assisted therapy.
Purpose of this study
The purpose of this study was to analyze interviews and responses with a small sample of individuals who had experiences with consuming synthetic psilocybin, a mycological extract, and/or entire Psilocybe mushrooms on separate occasions in a controlled clinical setting. The study aims to elucidate how individuals qualitatively describe and compare experiences with these different forms of psilocybin, which will address a major gap in the literature. It also seeks to understand whether synthetic psilocybin may be therapeutically similar to the consumption of the organic compound together with its co-occurring alkaloids and biological components.
For this study, a qualitative approach was undertaken to capture the experiences of participants in a holistic and nuanced way that is characteristically different from quantitative approaches. It is well known that qualitative methods can generate insight into an experience that would be difficult to capture using quantitative measures, especially for psychedelic experiences, which are highly complex and difficult to characterize (Barone et al., 2022; Davis et al., 2020). Furthermore, qualitative approaches are particularly useful for exploring new areas of research such as psychedelic phenomenology (Dunwoodie et al., 2023).
Method
Participants
Demographic data of the four participants is provided in Table 2. Interview participants were participants in the non-profit Roots To Thrive (RTT) Psychedelic Therapy program. They were referred to the program by end-of-life physicians due to anxiety or depression related to having a palliative care diagnosis. Participants were psychologically and physically screened to ensure they qualified for the treatment and did not endorse any exclusion criteria. Due to changing administration of exemptions in Canada, the participants in the first group session were legally allowed whole psilocybin mushrooms under a condition known as a section 56 exemption while participants in the second group session had a combination of people with section 56 exemptions and Special Access Program approval for synthetic psilocybin. The participants of the third and fourth group sessions all had Special Access approval for a mycological extract of whole Psilocybe mushrooms. All participants had previously consented to participate in research related to their experience with their RTT session (Fig. 1). Doses of synthetic and organic psilocybin for each participant is available in Table 3.
Race, age and gender of participants
| Race | Age | Gender |
| White | 65 | Female |
| White | 54 | Female |
| White | 56 | Male |
| White | 68 | Male |
Synthetic psilocybin and Psilocybe cubensis mushrooms before participants' dosing sessions
Citation: Journal of Psychedelic Studies 8, 3; 10.1556/2054.2024.00379
Form and dose of psilocybin experiences for each participant
| Participant | Form | Number of sessions | Dose |
| 1 | Whole Mushroom | Unknown* | 2 g |
| Mycological Extract | 1 | 25 mg | |
| 2 | Mycological Extract | 2 | 25 mg, 25 mg |
| Synthetic | 1 | 25 mg | |
| 3 | Whole Mushroom | 1 | 5 g |
| Mycological Extract | 1 | 25 mg | |
| Synthetic | 1 | 25 mg | |
| 4 | Whole Mushroom | 4** | 4 g, 5 g, 5 g, 7 g |
| Mycological Extract | 1 | 25 mg | |
| Synthetic | 1 | 25 mg |
Note. *Participant had 2-3 mushroom sessions on their own, separate from the program.
**Participant had a total of 4 whole mushroom sessions, 3 were private, and 1 session was with RTT.
Procedures
After screening, participants met online once a week for 2 h over 3–4 weeks with the therapy team (MDs, RNs, Energy/Somatic Therapists, Therapists, Spiritual Care) to get to know each other, learn about psilocybin and preparation, discuss their medical conditions, and form a community of practice with the other participants and the team and a shared intention for their psychedelic journey. On the day of the session, they met at the therapy center, had a physical exam, and then settled into the therapy room with the team to discuss intentions, strategies for overcoming challenging experiences known as ‘pillars of strength,’ and parameters around requests for support during the session. The ceremonial nature of the protocol was informed by the spiritual care expert and the program First Nation Elder (Dames, Kryskow, & Watler, 2022). This included participants having an opportunity to bless their medicine and ingest it thereafter. They then settled into their mats, with weighted and light blankets, pillows, eye masks and Bluetooth headphones with the same music playing on a speaker in the room. The therapy team provided support as needed.
At approximately the 4–5 h point when participants felt the major effects of the medicine had subsided, invitations were extended to partake in a share circle to discuss their experiences. Light snacks were shared afterwards which allowed conversations to continue. The group continued to integrate online in the next 1–2 days and met 2 h per week for another 3–4 weeks. The whole psilocybin mushroom session took place in November 2021. The combined whole mushroom and synthetic psilocybin session took place in April 2022. The mycologically extracted psilocybin mushroom session was in June 2023.
Interviewing
Two participants from the participant pool were identified as having experience with all three forms of psilocybin: whole P. cubensis mushrooms, synthetically made psilocybin and mycological extract of whole P. cubensis mushrooms. One participant had experience with whole P. cubensis mushrooms and mycological extract. The fourth had experience with synthetic psilocybin and the mycological extract containing a standardized amount of psilocybin. Participants were invited to reach out to the interviewer if they were interested in sharing their experience of the different forms. All four of the participants reached out and consented to recorded interviews. Interviewing was conducted during the summer of 2023 over the course of approximately 6 weeks. To maintain anonymity, complete demographic data of the four participants is not available. However, two identified as men and two identified as women.
Data analysis
The study employed thematic content analysis to identify recurring themes and exemplar quotes that were representative of the experiences of participants (Kyngäs, 2020). Two members of the research team independently coded transcripts and the results were cross-checked. Agreement was significant, however, a degree of disagreement was present surrounding the development of themes related to subjective effects and phenomenology. Consensus was achieved through iterative dialogue and the clinical team confirmed results of the analysis corresponded to their diagnostic impressions during treatment and follow-up interviewing.
This study seeks specifically to identify patterns in participants' experiences with each form of psilocybin to better understand in what ways they are similar and different from one another. As such, we opted to use thematic content analysis as this method is best suited to identify themes across all interviews (Braun & Clarke, 2021). While the recommended sample size for thematic content analysis ranges from 2 to over 400 (Fugard & Potts, 2015), other studies with sample sizes similar to ours have used this methodology (e.g., Hughes & Cassar, 2019; Nigro, 2018). Further, Fugard & Pots suggest that if a theme is highly prevalent in a population, a sample size of 4 or less will be sufficient to detect it. The research team chose to pursue this approach as opposed to other qualitative techniques such as interpretative phenomenological analysis (IPA), which focus more on subjective experiences, because study objectives were to identify themes among participant responses rather than interpret in-depth accounts of subjective effects of the drugs (Smith & Osborn, 2015).
Results
Themes
There were six discrete themes identified relating to the participant's experiences with the various forms of psilocybin. All themes were touched upon by every participant and reached a point of saturation in our analysis. The themes include (1) phenomenology and subjective effects (2) preference (3) emotional and psychological effects (4) spiritual and mystical experiences, (5) onset and comedown and (6) mild and transient side effects. For each theme, there were varying levels of consensus on the effects of the different forms (Table 4).
Verbal interviewee responses regarding their experiences with synthetic, mycological extract, and whole mushroom forms of psilocybin
| Theme | Description | Exemplar quotes |
| Phenomenology and Subjective Effects | Subjective sensory phenomena, such as visual and physical effects and perceptual distortions | Participant 1 (whole mushroom): “Things were brighter, green was greener, red was redder sort of thing. It was a brightness, a clarity, a cleanness.” |
| Participant 4 (mycological extract): “More kinetic in the experience, a little less visual.” | ||
| Participant 3 (synthetic): “It was like I was looking through a window, looking at it. I wasn't in it.” | ||
| Preference | Stating that they prefer a certain form of psilocybin over others | Participant 2 (whole mushroom): “I would (if given the choice) probably want the real mushroom, the whole mushroom.” |
| Participant 3 (whole mushroom): “The natural whole product is the mushroom, and for some reason human beings have to manipulate that. Let's just eat the mushrooms, the most natural way to go.” | ||
| Participant 4 (synthetic): “If all you have is synthetic, it'll get the job done but not a first choice.” | ||
| Emotional and Psychological Effects | Participant's emotions and therapeutic breakthroughs during and following the experience | Participant 1 (mycological extract and whole mushroom): “I think this drug heightens empathy” |
| Participant 2 (synthetic): “I talk about death and (do) not panic, and I process my emotions and I sit with them and let them affect me, and it doesn't hurt as much.” | ||
| Participant 3 (synthetic): “I was okay, and I was comfortable with it, but it didn't bring the emotion that (whole mushroom) did.” | ||
| Spiritual and Mystical Experiences | Experiences of bodily transcendence, unity or connection, increased spirituality, mushroom consciousness | Patient 2 (whole mushroom & mycological extract): |
| “The (mycological extract) was alive as well, but I think there's something still sort of sacred and alive with taking it as the mushroom itself.” | ||
| Participant 4 (synthetic): “It felt more medicine-y and less spiritual.” | ||
| Patient 4 (all forms): “In all three cases, my physical body largely ceases to exist.” | ||
| Onset and Comedown | The onset and the comedown from the experience | Participant 1 (mycological extract): “The takeoff was so rapid… The plane was up in the air pretty fast.” |
| Participant 4 (mycological extract and whole mushroom): “The botanical and the natural mushrooms have a more gentle onset to them.” | ||
| Participant 3 (synthetic): “I didn't get the boom. I think it was a slower introduction to it.” | ||
| Mild and Transient Side Effects | Negative or challenging experiences, lack of response, disappointment, and transient side effects that followed | Participant 2 (mycological extract): “At about 2 h… all I could feel was I'm not okay. And it sent me into a real panic.” |
| Participant 4 (mycological extract): “I had a significant chunk of anxiety at the onset of it.” | ||
| Participant 2 (synthetic): “And so while I felt differently inside, I didn't have an experience like everybody else did. I thought I failed.” |
Phenomenology and subjective effects
Participants described and compared qualitative differences related to vividness, acute perceptual effects, and other phenomenological qualities during their dosing experiences. Descriptions of subjective effects varied among participants and ranged from altered visual perception of the environment to having an out-of-body experience. Experiences with the whole mushroom were described as being bright, vibrant, and alive and similarly, experiences with mycological extract were described as clear and garish. In contrast, synthetic was described as less colourful, like looking through a window, and mechanical. Temporal elements were compared as well with variegated reports and some disagreement regarding whether the psychoactive effects of organic or synthetic forms were longer in duration. Temporarily coming in and out of the experience (an ebbing and flowing) was reported with the synthetic form and, to a lesser extent, the mycological extract, but not the whole mushroom.
Preference
There was consensus among participants that the preferred form was the whole mushroom. The reasons given for this include the feeling that the whole mushroom is sacred, alive, unmanipulated by humans and natural. Individuals found the whole mushroom and mycological extract forms to have a gentler onset and comedown, and cited this as a factor that made the forms superior to the synthetic variant. At the same time, the experience of synthetic psilocybin in pill form was described as feeling more like medicine and being a dummied-down experience that was generally viewed as inferior to the organic forms. Despite not being the first choice, participants agreed that synthetic psilocybin was still therapeutic. Some explained that during the peak of the experience, the different forms of psilocybin had the same effect.
Emotional and psychological effects
Emotional and psychological effects were reported by participants. During and following their psilocybin experiences, participants reported feeling heightened emotions, and empathy and compassion with all three forms. Overall, emotions experienced during the sessions were described as positive and empowering. Some spoke about the empowering feeling of joining generations of people who had taken psilocybin before them. In addition, participants spoke of breakthroughs in their emotional processing in their day-to-day lives following dosing sessions with both synthetic and whole mushrooms. There were reports of participants feeling more comfortable with death and using their psilocybin experiences as a touchstone to alleviate anxiety in moments of dysregulation. However, while synthetic psilocybin was described as therapeutic, this form was also reported as inducing less emotion and less euphoria compared to the whole mushroom.
Spiritual and mystical experiences
Another central theme that emerged was spiritual and mystical experiences with all three forms of psilocybin. Participants spoke of non-ordinary experiences of consciousness which included feelings of rebirth, feelings of unity with the universe, and feeling as if they ceased to exist. They also described feeling more spiritual, both during and following the session. Psilocybin delivered in pill form (mycological extract and synthetic) was perceived as less spiritual because participants felt it was manmade and less traditional. The texture of the synthetic experience was further described as mechanical rather than alive as with other forms. In contrast, while taking psilocybin in whole mushroom form, some felt connected to the cycle of life or felt as if they were participating in a ceremony. Experiences that were longer in duration (mycological extract and the whole mushroom) were also perceived as more spiritual in part because there was more time to go deeper. There was agreement among participants that the whole mushroom felt more sacred and spiritual than other forms.
Onset and comedown
Participants discussed the onset and comedown phases of their psychedelic dosing experiences. Their discussion revealed significant variation among participants' perceptions of each forms' respective onset and comedown phases. Synthetic, mycological extract and whole mushroom were all described as having a rapid and sharp onset by some, as well as a gentle and slow onset by others. For some participants, the transitional periods at the beginning and end of the experience were identical for both of the naturally derived forms when the whole mushroom was consumed with citrus juice. It was noted that a gentle transition period is more comfortable, can facilitate integration and allows for the ability to meditate into the experience. On the other hand, it was pointed out that too long of an onset can lead to anxiety if the participant doesn't have anything to occupy themselves with. Thus, there was also no consensus as to whether a sharp or gentle onset was superior. Some mentioned that beside the onset and comedown, the three forms are very similar to each other.
Mild and transient side effects
Transient side effects during the various dosing experiences were brought up at points during the interviews. Physical symptoms were scarcely mentioned and included mild nausea, which resolved on their own without intervention. In terms of emotional distress, participants cited external factors such as group dynamics as being influential. This included being affected by others' panic and feeling worried about people in the session who were crying out for help. Some complaints also included how the prolonged onset of the whole mushroom caused anxiety. A lack of response following the session was also associated with the feeling of failure for not having an experience that was as profound as everyone else.
Discussion
As far as we know, this sample contains the only individuals who have legally experienced three different forms of psilocybin, i.e., synthetic, mycological extract, and whole mushroom. Despite approximately 19 months between the first and the last sessions participants recalled with reasonable clarity their experience with each of the forms of psilocybin. Their experiences can help inform differences and similarities between these various forms, and the advantages and disadvantages of using each in the context of treatment. All three forms of psilocybin appear to boast a range of potentially therapeutic properties that alleviate psychiatric symptoms and disrupt psychopathological pathways in ways supported by the literature (Thomas, Malcolm, & Lastra, 2017). The finding of increased spirituality among participants is consistent with previous clinical trials (Griffiths, Richards, McCann, & Jesse, 2006, 2018; Malone et al., 2018). Likewise, Swift et al. (2017) and Agin-Liebe et al. (2020) have reported reductions in death-related anxiety after psilocybin experiences similar to those mentioned by participants of this study.
First-hand testimony of preference for organic whole Psilocybe mushrooms over the synthetic compound as found in the present study suggests that clinical research should consider exploring the tolerability, safety, and efficacy of both forms. It is notable that there was consensus among participants that the whole mushroom felt more sacred, spiritual and ceremonial as the literature suggests that spiritual practices are associated with psychological well-being (Bożek, Nowak, & Blukacz, 2020; Verghese, 2008). Given this, the whole mushroom form may have a superior therapeutic effect, although further research is required to confirm this. Certain issues would arise while using the whole mushroom, particularly the difficulties surrounding the precise dosing of active compounds. This study suggests there may be a hierarchy and each experience is distinct in its own way. Complaints regarding synthetic mushrooms were primarily related to their harsh onset and rapid comedown, artificial texture, and overall inferior quality.
Call to action
Research on novel compounds in the field of psychedelic medicine has primarily focused on synthetic compounds like psilocybin, MDMA, DMT, and a range of analogues (Ali et al., 2023; Sherwood et al., 2020a, 2020b; Smith, Sicignano, Hernandez, & White, 2022). This bias in research is likely due to a range of factors and is heavily influenced by profitability, the need to discover patentable drugs, and Western empiricism (Ghijsen, 2009; Van Court et al., 2022; Wong & Chan, 2014). Additionally, synthetic compounds are largely exclusive, and not accessible to patients with no funds or access to trials (Elkordy, Haj-Ahmad, Awaad, & Zaki, 2021). It is also important to acknowledge and honor the experience of traditional knowledge keepers who have used visionary fungi for millennia. Indeed, groups such as Indigenous populations may preferentially or exclusively use whole mushrooms in ceremonial and healing practices. Limiting research to the impact of synthetic compounds therefore excludes these groups from scientific findings, creating additional barriers to establishing equity.
Our present study demonstrates that there are indeed perceived differences between forms of psilocybin. It highlights which aspects of the psychedelic experience may differ, such as the onset, comedown, and spiritual and psychological effects, which we can seek to better understand in future research. This knowledge can be, in turn, used to inform decisions of patients and clinicians using psilocybin in a clinical setting and lay the basis to determine which form has the highest tolerability and highest therapeutic effect to maximize its efficacy amid the rise of mental illness diagnosis' (Wiens et al., 2020).
Limitations
Limitations to this study include the variability regarding the dose of psilocybin and other active alkaloids for individuals describing their experiences with whole Psilocybe mushrooms. However, all participants reported having ingested enough to have an experience in the ‘psychedelic’ range of dosing. Additionally, co-administration of fruit juices may have influenced participants' experiences of drug onset and comedown as citric juice assists in the conversion of psilocybin to psilocin while also commonly intensifying the experience, leading to shorter duration, and increasing onset speed. Another limitation is that interviews required participants to recall psychedelic experiences that were 19 months apart, which may have impaired their ability to accurately recall their memories of the event. At the same time, research indicates that psilocybin experiences have high degrees of personal significance and are often very memorable (Griffiths et al., 2006). Lastly, it is important to note that this study involved a small sample size. While a sample size of 4 is unusual and less than the current guidelines for thematic content analysis (Braun & Clarke, 2013), the pool of eligible participants for the study was extremely limited. However, it has been argued that sample sample sizes are still useful for demonstrating the presence of an effect (Anderson & Vingrys, 2001). In addition, the sample lacks diversity, being an all-White sample, which limits generalizability. Ultimately, research must be carried out to determine the differences and similarities in reports of psilocybin experiences.
Future research directions
With the rising prevalence of depression, anxiety and PTSD, psilocybin has emerged as a promosing treatment option (Carhart-Harris et al., 2016; Gukasyan et al., 2022; Wiens et al., 2020; Wu et al., 2023). As such, it is crucial to understand how forms of this compound differ to advise both clinicians and patients and maximize treatment efficacy. Future research can pick up where this paper leaves off and explore more deeply why experiences with whole Psilocybe mushrooms may be different from synthetic psilocybin. This could include more detailed surveys and qualitative interviewing, as well as pharmacological research into the chemical makeup of Psilocybe mushrooms, the effects of its many alkaloids, and the possibility of an entourage effect being the underlying cause for its superior therapeutic quality and experiential effects. Ultimately a double-blind, placebo-controlled, randomized clinical trial should be conducted to determine if statistically significant improvements can be detected in PAT where whole Psilocybe mushrooms replace synthetic psilocybin.
Declaration of interests
Dr. Pamela Kryskow is the Medical Lead of Roots To Thrive Non-Profit, is the current President of the Non-Profit Board, is a paid advisor for Mycomedica Life Sciences Public Benefit corporation, an unpaid advisor for Synaptic in Oregon and Nectara in British Columbia, a clinical advisor for Numinus compensated by future warrants, a clinical instructor in the Department of Family Medicine at the University of British Columbia, an adjunct professor at Vancouver Island University and the Medical Chair of the Post Graduate Certificate in Psychedelic Assisted Therapy at Vancouver Island University.
Dr. Joseph La Torre, Ph.D. is Lead Research Psychologist at the Center of Novel Therapeutics in Addiction Psychiatry at UW Medicine, Department of Psychiatry and Behavioral Science and is funded by Washington State via SB 5236. He is also Clinical Advisor at Oregon Psychedelic Institute and an instructor in the School of Psychology, University of Ottawa.
Paul Stamets is the author of 6 books describing psilocybin, is the majority shareholder of MycoMedica Life Sciences, PBC which is developing psilocybin for therapeutic use and has been awarded several patents on psilocybin use and compositions.
Katherine Sattler is a third-year undergraduate student at the University of British Columbia, specializing in neuroscience.
Dr. Vivian WL Tsang is the Research Lead of Roots to Thrive Non-Profit and the Research Director of the Naut sa Mawt Psychedelic Center. She holds an Adjunct Professorship through Vancouver Island University and is funded by a MITACS grant. She is the Chair of the Board of Directors of Qi Integrated Health, a private clinic offering ketamine assisted therapy.
Dr. Monnica Williams, PhD is the Canada Research Chair for Mental Health Disparities at the University of Ottawa in the School of Psychology. She is also the Clinical and Training Director of the Behavioral Wellness Clinics. Dr. Williams served as the PI for a grant-funded Phase 2 study of MDMA for PTSD, with a focus on culturally-informed treatment for people of color. She has served as Chair of the Board of Directors for the Chacruna Institute for Psychedelic Plant Medicines and the Board of Psychedelic Medicines and Therapies.
Funding
There was no funding for this paper across the board.
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