Written evidence submitted by Professor Jo Neil, Dr. Sara Tai and Dr. John Gigg (DRU0062)


1. This submission of evidence will address the topic of psychedelics – specifically psilocybin – and their current legal status within the UK’s drug laws. It will lay out the facts about psilocybin and other psychedelics, including their potential as significantly effective treatments for a range of serious mental health problems, and make the economic, health, and scientific case for reforming the UK’s drug scheduling laws to enable more research into the therapeutic effects of these substances.


2. Medical psychedelic research has undergone a renaissance in recent years. Psychedelics include plant medicines such as psilocybin (the active constituent of magic mushrooms), Ayahuasca (a powerful psychedelic used by indigenous populations, made from Banisteriopsis caapi vine, and often consumed as a tea), and those synthesised in the laboratory, including Lysergic acid diethylamide (LSD) and MDMA (ecstasy).

3. Medicines derived from psychedelics are, in recent small-scale clinical studies, proving to be very effective for hard-to-treat or hard-to-cure psychiatric difficulties[2], such as severe depression[3], anxiety and depression that occurs in terminal cancer patients, alcohol dependence[4] and smoking[5], and OCD (obsessive compulsive disorder).[6] Most recently, evidence is emerging for the efficacy in PTSD (post-traumatic stress disorder).[7]

4. Our focus is on psilocybin, as the psychedelic drug with most clinical evidence for its effectiveness for severe depression. Psilocybin is a naturally occurring molecule found in over 200 species of fungi. It is structurally similar to serotonin – a human neurotransmitter that has a role in the regulation of mood and perception. When administered in clinical settings with psychological support, early clinical trials show that psilocybin may be a safe and effective treatment for many mental health problems[8], particularly for patients for whom other treatments have been ineffective. Psilocybin has very low toxicity and no detrimental short- or long-term effects on cognitive function or emotional processing[9].

5. Unfortunately, researching psychedelics is particularly difficult in both human and animal studies. It is extremely costly, bureaucratic, and incurs large time delays due to the drug control conventions of 1960 and 1971.[10],[11],[12],[13] These conventions detail the scheduling of different controlled drugs. Drugs are divided into five schedules, each specifying the requirements governing such activities as import, export, production, supply, possession, and record keeping which apply to them, for example in research-based circumstances.

The current status of psilocybin

6. Psilocybin is currently in Schedule 1, while some drugs that are in Schedule 2 with less stringent control – are heroin, fentanyl, cocaine, and ketamine; which are potentially extremely dangerous.

7. For substances in Schedule 1, a Home Office licence is generally required for their production, possession, or supply. This involves an assessment of laboratories by Home Office staff, which is a time-consuming process that can take up to six months. This process has been further delayed by COVID-19, with the Home Office ceasing to carry out checks. Current license holders have been able to continue using their existence licenses, but the application process for prospective researchers has become even more difficult. A controlled drug register must be used to record details of any Schedule 1 controlled drugs received or supplied by a licensed supplier. The drug has to be destroyed after use, under supervision by a qualified person, e.g. specialist pharmacist.

8. Researchers seeking to work on potential new treatments for treatment resistant depression (TRD) using psilocybin face burdensome additional costs (£3,000 for a new licence) and delays (up to one year in some cases),13 due to its classification as a Schedule 1 substance. This is in spite of existing evidence of its safety, medical benefit and its potential as the basis for new treatments for depression8. This delay and cost is compounded by the time taken for necessary ethical and Home Office processes to obtain a license to carry out research programme – typically at least 1 year for a new license, and 4-6 months to amend an existing license.

9. Scheduling is not merely a theoretical issue – it determines which research projects researchers choose to consider, which get approved, and how billions of pounds of R&D funds in the UK and international pharma industry are committed. The status of psilocybin in Schedule 1 creates costly and time-consuming bureaucracy before research can even begin, restricting the potential of the UK’s smaller research institutions and pharmaceutical companies in contributing to this emerging area.

10. In order to enable this research in the UK, this Government needs to move psilocybin from Schedule 1 to Schedule 2 of the 1971 Misuse of Drugs Act.

There is no evidence to support psilocybin being in Schedule 1

11. Risk reviews have consistently shown that, provided participants are psychologically prepared and take drugs derived from psychedelics in a controlled setting, the effects can be significantly beneficial. Psychedelics have a low physiological risk when used outside of a clinical setting[14] to users and society.[15] It is also notable that some of the substances in lower Schedules than psychedelics include heroin, cocaine, and ketamine – which are all managed responsibly by research staff. Schedule 1 is reserved for substances with no medical value – whereas psilocybin clearly has such value.8

12. Science has moved on, there is now sufficient evidence of potential medical benefit for medicines derived from psychedelics. Moving psychedelics from Schedule 1 to a lower Schedule would enable our drug regulations to continue working in the way that they were intended allowing medical and pharmaceutical research, and continuing to guarantee secure and responsible stewardship of substances in a small number of properly regulated organisations.

13. By rescheduling psilocybin to Schedule 2, many opportunities can be realised. There will be benefits, not just in the field of health and social care, but also research leadership, industrial, and financial rewards.

Psilocybin and other psychedelics are already being rescheduled in other countries

14. Many other countries – including the US – have relaxed controls on psilocybin to enable research. The FDA has also fast tracked MDMA for treatment of PTSD, and Psilocybin for severe depression. Psilocybin is derived from fungi native to the UK, which – combined with research expertise and funding – means there is huge potential for the UK to tap into a lucrative market.[16]

A majority of the public support changing the law for compassionate access

15. 68% of respondents to a YouGov survey[17] supported changing the law to allow people with terminal illnesses access to psilocybin-assisted therapy. 55% also supported changing the law to allow psilocybin-assisted therapy in combat veterans suffering from PTSD, depression, and anxiety. Canada has successfully achieved access for terminally ill patients via access approved Section 56 exemptions from the Minister of Health. Although on a case by case basis and still slow, this has to date enabled 55 patients across Canada to access legal psilocybin-assisted psychotherapy.[18] The US state of Oregon voted to establish a system allowing the medical use of psilocybin in 2020, passing ballot measure 109.[19] This is a landmark change in US law.

Benefits of rescheduling

Mental health

16. The most obvious benefit of rescheduling is that research can more easily be conducted into the effectiveness of psilocybin for mental health treatments. Mental health has reached crisis levels during the COVID-19 pandemic.[20] 21% of adults experienced depression during 27 January to 7 March 2021; an increase of 11% from pre-COVID levels (10%).[21]

17. Psilocybin-assisted therapy is arguably the most promising innovation for the treatment of depression seen for decades, with greater than 70% long-term efficacy in small scale trials.[22] These long-term effects could result in a reduction in future spending on mental health treatments, and can also contribute to workforce health and productivity.

18. Poor mental health currently costs the UK economy upwards of £100 billion per year due to losses in productivity[23]. By using psilocybin as a long-term strategy, it has the potential to solve these interlinked problems in one go. Recent research in small trials has shown that psilocybin-assisted therapies may also be used safely and be effective for substance-misuse disorders[24], end-of-life anxiety,[25],[26] and obsessive-compulsive disorder.[27]

19. There has been little to no innovation in psychiatry in over 50 years – the age of selective serotonin reuptake inhibitors (SSRIs), which are the most commonly prescribed antidepressants. This must be seen in the wider context of NHS mental healthcare, where patients are frequently put on long waiting lists for cognitive behavioural therapy (CBT), and are likely to be prescribed SSRIs in this time as well.

20. Only 36.8% of patients experience remission despite being prescribed SSRIs.[28] Jakosbsen and colleagues conducted a systematic review of evidence for SSRIs versus placebo, including 131 trials and 27,422 participants, and reported that although the short-term effects (3-month) of SSRIs were better than placebo, this effect was still below the threshold of clinical significance.[29] The benefits of SSRIs were even lower in the longer term.

21. This evidence was updated in 2020,[30] concluding that antidepressants should not be used for adults with depression due to the minimal benefits and the increased risk of serious and non-serious adverse events, including serious problems with dependency, unwanted side effects, and increased suicide risk.[31]

22. While psychedelic assisted therapies could contribute to a general improvement in mental health outcomes, it could also have enormous benefits for service veterans.[32] Currently, some veterans who return from active duty suffer from mental health problems; most commonly PTSD. The treatments that the UK has to offer frequently ineffective, so these veterans seek help elsewhere. Many UK veterans make use of psilocybin retreats in the Netherlands[33] – where psilocybin is legal – to self-treat their own mental health difficulties. This is treatment that should be offered in the UK, for UK veterans, within our safe and medically-supported healthcare system.


23. Although there are substantial benefits for mental health, rescheduling psilocybin makes economic sense too. The Government has identified life sciences and pharmacy as flagship UK industries in the post-Brexit period,[34] within which rescheduling psilocybin could be a large component. For years now, the UK has been falling behind many other countries on research and development spending.[35] The window is closing to be an international leader, with competition from the US[36], Germany[37]and others, as there will be a ‘first in market’ advantage for whoever acts decisively to enable this research at scale. In doing so, the potential for new research jobs, both in higher education and in industry, is created, contributing further to the UK’s productivity.

24. Psychedelics represent a lucrative market. The combined value[38] [p20] of medical psychedelics companies in October 2021 was over US$10 billion. Medical psychedelics have a market value of US$190 million, which is expected to rise to US$2.4 billion by 2026.38 The UK has the research and industrial infrastructure, and the scientific expertise, to claim a large share of this market – but only if psilocybin and other psychedelics are rescheduled to enable wider research into these potentially life-saving medicines.

March 2022

[1] Mental Health Taskforce NE. The Five Year Forward View for Mental Health, 2016

[2] https://pubmed.ncbi.nlm.nih.gov/27067625/

[3] https://www.nejm.org/doi/full/10.1056/NEJMoa2032994

[4] Bogenschutz MP, Forcehimes AA, Pommy JA, Wilcox CE, Barbosa PCR, Strassman RJ. Psilocybin-assisted treatment for alcohol dependence: a proof-of-concept study. Journal of psychopharmacology. 2015;29(3):289-99.

[5] Johnson MW, Garcia-Romeu A, Cosimano MP, Griffiths RR. Pilot study of the 5-HT2AR agonist psilocybin in the treatment of tobacco addiction. Journal of psychopharmacology. 2014;28(11):983-92

[6] Moreno FA, Wiegand CB, Taitano EK, Delgado PL. Safety, tolerability, and efficacy of psilocybin in 9 patients with obsessive-compulsive disorder. Journal of Clinical Psychiatry. 2006;67(11):1735-40

[7] https://academic.oup.com/ijnp/article/23/6/385/5805249

[8] Nichols DE. Psilocybin: from ancient magic to modern medicine. The Journal of Antibiotics.

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[9] Rucker, J. J., Marwood, L., Ajantaival, R. L. J., Bird, C., Eriksson, H., Harrison, J., ... & Young, A. H. (2019). The effects of psilocybin on cognitive and emotional functions in healthy participants: results from a phase 1, randomised, placebo-controlled trial involving simultaneous psilocybin administration and preparation. Journal of Psychopharmacology, 02698811211064720.

[10] https://www.unodc.org/unodc/en/commissions/CND/conventions.html

[11] Rucker J (2015) Psychedelic drugs should be legally reclassified so that researchers can investigate their therapeutic potential. BMJ 350(May 26 20): h2902

[12] Rucker J, Schnall J, D’Hotman D, King, D, Davis, T., Neill, JC. (2020) Medicinal use of psilocybin: reducing restrictions on research and treatment. Report by CDPRG and the Adam Smith Institute, https:// www.cdprg.co.uk/psilocybin.

[13] Howard A, Neill JC, Schlag AK, Lennox C (2021) Schedule 1 barriers to research in the UK: an in-depth qualitative analysis. Drug Science Policy and Law, 7: 1-13.

[14] Schlag, A. K., Aday, J., Salam, I., Neill, J. C., & Nutt, D. J. (2022). Adverse effects of psychedelics: From anecdotes and misinformation to systematic science. Journal of Psychopharmacology, 02698811211069100.

[15] Nutt, DJ, King, LA, Phillips, LD (2010) Drug harms in the UK: A multicriteria decision analysis. The Lancet 376 (9752): 1558–1565.

[16] https://psilocybinalpha.com/psilocybin-stocks-shroom-stocks

[17] https://www.drugscience.org.uk/uk-psilocybin-support-yougov-poll/

[18] https://therapsil.ca/about/

[19] http://oregonvotes.org/irr/2020/012text.pdf

[20] https://www.health.org.uk/news-and-comment/news/latest-data-highlights-a-growing-mental-health-crisis-in-the-uk

[21] https://www.ons.gov.uk/peoplepopulationandcommunity/wellbeing/articles/coronavirusanddepressioninadultsgreatbritain/julytoaugust2021

[22] https://psilocybin.health/psilocybin

[23] https://www.centreformentalhealth.org.uk/news/centre-mental-health-calls-government-set-budget-wellbeing-cost-mental-ill-health-england-reaches-ps119-billion

[24] Bogenschutz, M. P. (2017). It’s time to take psilocybin seriously as a possible treatment for substance use disorders. The American journal of drug and alcohol abuse, 43(1), 4-6.

[25] Grob CS, Danforth AL, Chopra GS, Hagerty M, McKay CR, Halberstadt AL, et al. Pilot study of psilocybin treatment for anxiety in patients with advanced-stage cancer. Archives of general psychiatry. 2011;68(1):71-8.

[26] Ross, S., Bossis, A., Guss, J., Agin-Liebes, G., Malone, T., Cohen, B., ... & Schmidt, B. L. (2016). Rapid and sustained symptom reduction following psilocybin treatment for anxiety and depression in patients with life-threatening cancer: a randomized controlled trial. Journal of psychopharmacology, 30(12), 1165-1180.

[27] Moreno, F. A., Wiegand, C. B., Taitano, E. K., & Delgado, P. L. (2006). Safety, tolerability, and efficacy of psilocybin in 9 patients with obsessive-compulsive disorder. The Journal of clinical psychiatry, 67(11), 18864.

[28] Rush, A. J., Trivedi, M. H., Wisniewski, S. R., Nierenberg, A. A., Stewart, J. W., Warden, D., ... & Fava, M. (2006). Acute and longer-term outcomes in depressed outpatients requiring one or several treatment steps: a STAR* D report. American Journal of Psychiatry, 163(11), 1905-1917.

[29] Jakobsen, J. C., Katakam, K. K., Schou, A., Hellmuth, S. G., Stallknecht, S. E., Leth-Møller, K., ... & Gluud, C. (2017). Selective serotonin reuptake inhibitors versus placebo in patients with major depressive disorder. A systematic review with meta-analysis and Trial Sequential Analysis. BMC psychiatry, 17(1), 1-28.

[30] Jakobsen, J. C., Gluud, C., & Kirsch, I. (2020). Should antidepressants be used for major depressive disorder?. BMJ evidence-based medicine, 25(4), 130-130.

[31] Hengartner, M. P., & Plöderl, M. (2019). Newer-generation antidepressants and suicide risk in randomized controlled trials: a re-analysis of the FDA database. Psychotherapy and psychosomatics, 88(4), 247-248.

[32] https://www.heroicheartsuk.com/about

[33] https://www.synthesisretreat.com/

[34] https://www.gov.uk/government/news/bold-new-life-sciences-vision-sets-path-for-uk-to-build-on-pandemic-response-and-deliver-life-changing-innovations-to-patients

[35] https://www.bbc.co.uk/news/science-environment-58965036

[36] https://jamanetwork.com/journals/jamapsychiatry/fullarticle/2772630

[37] https://www.zi-mannheim.de/en/research/departments-research-groups-institutes/molecular-neuroimaging/efficacy-and-safety-of-psilocybin-in-treatment-resistant-major-depression-episode.html

[38] https://psych.global/wp-content/uploads/2021/10/PSYCH_THE_PSYCHEDELICS_AS_MEDICINE_REPORT_3rd_Edition.pdf