Psilocybin-assisted therapy is being investigated for anorexia nervosa as a possible way to reduce entrenched psychological symptoms and support engagement with recovery. Early findings suggest that some patients experience changes in eating-disorder concerns or motivation. These changes must be considered alongside nutrition, physical health, psychiatric risk and sustained everyday functioning.
Psilocybin is an experimental intervention for anorexia nervosa. Psychological improvement does not automatically establish nutritional recovery or medical safety. Specialist eating-disorder care remains central before, during and after any participation in research.
On this page
- A disorder affecting mind and body
- What psilocybin might change
- The early clinical evidence
- Interpreting improvement without overstating it
- Medical vulnerability changes the safety assessment
- Psychiatric risk continues after the session
- Therapeutic boundaries and the interpretation of experience
- The role of continuing eating-disorder treatment
- Who remains outside the evidence
A disorder affecting mind and body
Anorexia nervosa is a serious eating disorder involving restricted energy intake, intense fear of weight gain or persistent behaviour preventing it, and disturbances in the experience or evaluation of weight and shape. It is not a lifestyle choice. Eating disorders can affect people across demographic groups, and the distress associated with them may not be obvious to others.1
Psychological and physical difficulties can reinforce one another. Food-related fear, rigid rules and a sense of threat around change may make treatment difficult to tolerate. Malnutrition can itself affect concentration, emotional regulation and physical functioning. Care must address this interaction without reducing the illness to either a purely psychological problem or a number on a scale.2
Ambivalence about recovery also deserves careful interpretation. Someone may want relief from exhaustion, isolation or preoccupation while remaining frightened of the changes that recovery involves. This is a clinical difficulty to work with compassionately, rather than evidence that the person does not deserve help or is choosing to remain unwell.
What psilocybin might change
Psilocybin is converted to psilocin, which acts at serotonin receptors, especially 5-HT2A. Its acute effects can alter emotion, perception and the sense of self.34 Potential therapeutic targets in anorexia nervosa include rigid patterns of thinking, fear associated with eating and weight restoration, self-criticism and difficulty imagining a life less organised around the illness.
These are proposed targets, not established mechanisms of recovery. Evidence that psychedelics can affect neural plasticity does not demonstrate that they reverse the biological consequences of malnutrition. Nor does a temporary experience of self-compassion establish that someone can maintain adequate nutrition when food-related fear returns.5
A useful psychological change would help the person participate in recovery over time. It might make a difficult conversation possible, increase willingness to accept support or reduce the authority of a rigid rule. Such possibilities need to be assessed through subsequent behaviour and health, rather than inferred from the intensity of the session.
The early clinical evidence
A 2023 phase 1 study treated ten adult women with anorexia nervosa or partial remission using a supported psilocybin session. Its primary purposes were to examine safety, tolerability and feasibility. Some eating-disorder concerns improved, but the pattern of change was not uniform across outcomes.6
At three months, four participants had global Eating Disorder Examination scores within one standard deviation of community norms. This was a measure of eating-disorder psychopathology, not confirmation that four participants had achieved full clinical recovery. The study found no statistically significant average change in body mass index. Half the sample had already been in partial remission, further limiting generalisation to more acutely ill patients.6
A 2026 pilot enrolled 21 adult women in a six-week programme with three sessions in a fixed order, alongside psychological support and usual care. Eating-disorder symptom scores improved at six months and motivation-related scores at twelve months, with substantial variation between participants. There was no randomised parallel comparison. The findings therefore cannot separate psilocybin’s contribution from other care, expectations or change over time.7
A lower questionnaire or interview score can be valuable while physical illness remains. Recovery also requires attention to adequate nutrition, medical stability, daily functioning and the ability to sustain change. No single psychological score can establish all of these outcomes.
Interpreting improvement without overstating it
Open-label and small exploratory studies can establish whether a treatment can be delivered and whether further investigation is justified. They are less able to determine how much improvement would have occurred without the experimental intervention. Participants may be highly motivated, receive substantial attention and continue other treatment throughout follow-up.
Baseline differences also matter. A person already in partial remission may have different treatment needs from someone with severe medical instability. Combining these patients in a small study can obscure important differences. An average improvement does not mean that every participant improved, and the absence of a statistically significant effect does not prove that no individual changed.
| Outcome | Potential clinical meaning | Limit of the inference |
|---|---|---|
| Reduced eating-disorder concerns | Less distress or preoccupation involving food, weight or shape. | Does not alone establish adequate nutrition. |
| Greater motivation to change | More willingness to consider or engage with treatment. | Does not establish sustained changes in behaviour. |
| Medical stabilisation | Improvement in immediate physical risk. | Does not mean that psychological symptoms have resolved. |
| Improved daily functioning | Greater participation in relationships, work or education. | Needs follow-up alongside physical and psychiatric health. |
Future trials should measure these domains together. A treatment that improves motivation but does not support nutritional rehabilitation may have a limited or adjunctive role. Conversely, psychological benefit may become more useful when it is accompanied by accessible specialist care and a realistic plan for maintaining change.
Medical vulnerability changes the safety assessment
Safety findings from otherwise healthy volunteers cannot simply be transferred to anorexia nervosa. Malnutrition may be associated with low blood pressure, a slow pulse, abnormalities in electrolytes, reduced physiological reserves and changes affecting cardiac risk. The nature and severity of these problems require individual medical assessment.2
Psilocybin can transiently increase pulse and blood pressure and can cause nausea, dizziness or headache. Those effects may have different implications in a medically vulnerable patient. A reassuring subjective experience does not establish normal glucose, electrolyte balance or cardiovascular stability. Clinical monitoring therefore cannot depend solely on how comfortable the person appears.28
In the 2023 feasibility study, two participants developed asymptomatic hypoglycaemia that resolved within 24 hours. No serious adverse events were reported, but this finding illustrates why nutritional and metabolic safeguards matter even when an intervention appears well tolerated.6
Fainting, confusion, chest symptoms, severe weakness or other signs of deterioration require prompt medical assessment. Psychedelic treatment is not a substitute for stabilisation. Decisions about nutrition, hydration and refeeding in a medically compromised patient belong within qualified clinical care.9
A research session must accommodate the patient’s nutritional and medical needs. Assumptions imported from non-clinical psychedelic settings, including prolonged fasting, may be inappropriate. The relevant standard is an individual plan made by clinicians familiar with both the eating disorder and the experimental intervention.2
Psychiatric risk continues after the session
The 2026 pilot reported two suicide attempts by one participant approximately seven and nine months after the final study visit. Investigators judged them unlikely to be related to psilocybin. These events do not establish drug causation, but they underline the need for continuing psychiatric care and follow-up beyond the immediate treatment period.7
Assessment should include mood, hopelessness, previous self-harm, current suicidal thinking and available support, alongside eating-disorder symptoms. A person can describe a session positively and still become distressed later. Early enthusiasm should not lead to reduced access to care or an assumption that risk has permanently resolved.
Disappointment also needs to be anticipated. When an experimental treatment has been presented as a final opportunity, non-response may feel especially difficult. Consent and preparation should leave room for no benefit, mixed benefit or deterioration. Further care must remain available without implying that a patient failed to engage correctly.
Therapeutic boundaries and the interpretation of experience
Altered states can generate vivid images, strong convictions or experiences that feel like recovered memories. Their emotional significance can be explored without treating them as independent verification of a historical event. Memory-like experiences under psilocybin do not establish previously unknown trauma, and leading questions can increase the risk of an unsupported interpretation.1011
Care should not require an explanation in which all eating-disorder symptoms originate from a hidden event. Patients differ in their histories, and therapeutic discussion should follow what can be responsibly established. A clinician can respond compassionately to distress while retaining uncertainty about the literal meaning of an experience.
Consent also includes clear boundaries around touch, privacy, disclosure and the patient’s freedom to disagree. Psychological vulnerability should not become a reason to privilege a therapist’s interpretation over the patient’s account. Meaningful support leaves room for doubt and does not demand gratitude, spiritual belief or a narrative of transformation.
The role of continuing eating-disorder treatment
NICE recommends specialist psychological treatment for adults with anorexia nervosa, with options including eating-disorder-focused cognitive behavioural therapy, MANTRA and specialist supportive clinical management. Care also addresses nutrition and physical monitoring; treatment decisions should not be based on body mass index alone. Medication should not be offered as the sole treatment.12
If psilocybin eventually proves useful, its likely place will need to be defined within this wider system of care. A psychologically important experience does not replace dietetic support, assessment of medical complications or help with the practical demands of recovery. Coordination between the research team and the usual treating team is therefore essential.
Medication changes require particular care. Discontinuing a prescribed medicine to enter a trial may carry risks unrelated to the psychedelic itself, including withdrawal or recurrence of symptoms. The decision requires an individual assessment and a plan agreed with the prescriber.13 Access to ordinary treatment should continue if participation is unsuitable or the patient chooses not to proceed.
Who remains outside the evidence
The published pilots discussed here involved adult women. Their findings do not establish efficacy or safety for children, adolescents, men, medically unstable patients or other eating-disorder diagnoses. A 2026 protocol describes research involving adolescents and young adults, but a protocol is a plan rather than evidence of benefit.14
Larger controlled studies need to examine nutritional recovery, functioning, relapse, adverse events and the burden of treatment alongside symptom scores. They should also explain who could not participate and why. Exclusion criteria affect both apparent safety and the relevance of results to specialist services caring for complex patients.
Psilocybin may eventually offer some patients an additional route into psychological change. At present, its promise must be judged against a demanding clinical standard: whether change can be sustained while nutrition, physical health and psychiatric wellbeing improve together.
References
- National Institute of Mental Health. Eating Disorders: What You Need to Know. Health information; accessed 11 October 2026.
- Downey AE, Chaphekar AV, Woolley J, et al. Psilocybin therapy and anorexia nervosa: a narrative review of safety considerations for researchers and clinicians. J Eat Disord. 2024;12:49. doi:10.1186/s40337-024-01005-z.
- Nichols DE. Psychedelics. Pharmacol Rev. 2016;68:264–355. doi:10.1124/pr.115.011478.
- Otto ME, van der Heijden KV, Schoones JW, et al. Clinical Pharmacokinetics of Psilocin After Psilocybin Administration: A Systematic Review and Post-Hoc Analysis. Clin Pharmacokinet. 2025;64:53-66. doi:10.1007/s40262-024-01454-4.
- de Vos CMH, Mason NL, Kuypers KPC. Psychedelics and Neuroplasticity: A Systematic Review Unraveling the Biological Underpinnings of Psychedelics. Front Psychiatry. 2021;12:724606. doi:10.3389/fpsyt.2021.724606.
- Peck SK, Shao S, Gruen T, et al. Psilocybin therapy for females with anorexia nervosa: a phase 1, open-label feasibility study. Nat Med. 2023;29:1947-1953. doi:10.1038/s41591-023-02455-9.
- Douglass HM, Spriggs MJ, Godfrey K, et al. Psilocybin therapy for adult females with anorexia nervosa: pilot study. Br J Psychiatry. Published online 8 July 2026:1–9. doi:10.1192/bjp.2026.10687.
- Yerubandi A, et al. Acute Adverse Effects of Therapeutic Doses of Psilocybin: A Systematic Review and Meta-Analysis. JAMA Netw Open. 2024;7:e245960. doi:10.1001/jamanetworkopen.2024.5960.
- Royal College of Psychiatrists. Medical Emergencies in Eating Disorders: Guidance on Recognition and Management. College Report CR233; accessed 11 October 2026.
- Kangaslampi S, Wolff M, Doss MK, et al. Questioning the recovery of dissociated traumatic memories under psilocybin: comment on "Therapeutic emergence of dissociated traumatic memories during psilocybin treatment for anorexia nervosa". J Eat Disord. 2025;13:278. doi:10.1186/s40337-025-01484-8.
- McGovern HT, Grimmer HJ, Doss MK, et al. An Integrated theory of false insights and beliefs under psychedelics. Commun Psychol. 2024;2:69. doi:10.1038/s44271-024-00120-6.
- National Institute for Health and Care Excellence. Eating disorders: recognition and treatment (NG69). Recommendations; accessed 11 October 2026.
- Halman A, et al. Drug–drug interactions involving classic psychedelics: A systematic review. J Psychopharmacol. 2024. doi:10.1177/02698811231211219.
- Sjöström D, Schau Rybäck O, Claesdotter Knutsson E, et al. Study Protocol for "Exploring the safety and therapeutic potential of psilocybin in the treatment of anorexia nervosa in adolescents and young adults". PLoS One. 2026;21:e0352246. doi:10.1371/journal.pone.0352246.