Professor Jo Neill
Professor of Psychopharmacology at the University Manchester and Chair of the Drug Science Medical Psychedelics Working Group
Medical psychedelic research has undergone a renaissance recently1. Studies have shown a remarkable response in neurological and hard to treat mental health conditions.
Psychedelics include plant medicines such as psilocybin (the active constituent of magic mushrooms), Ayahuasca (a South American psychoactive brew containing DMT,N-dimethyltryptamine-and monoamine oxidase inhibitors, often consumed as a tea), mescaline (from the Peyote cactus) and those synthesised in the laboratory including LSD and MDMA (ecstasy).
These medicines are, in recent small-scale clinical studies, proving to be effective for certain neurological and hard to treat psychiatric conditions including severe depression, anxiety and depression experienced by terminal cancer patients, alcohol and nicotine dependence, OCD and, most recently, PTSD (post-traumatic stress disorder).
A new landmark brain imaging study2 proposes a brain resetting mechanism of action for psilocybin in treatment resistant depression. Beneficial effects of psychedelics are long-lasting; one potential mechanism for this is enhanced neurogenesis, as shown in animal studies.3
The medical model
Psychedelics have proven remarkably safe when used in a clinical setting where the paradigm is treatment with one or two high doses preceded and followed by extensive psychotherapy. This integration is essential to enable the patient to make sense of the experience and to gain maximum and lasting effects.
For patients with severe depression to respond to one or two doses of a drug with such lasting benefits is remarkable.
The medical model for treatment of neurological conditions is rather different and involves low non-psychedelic doses taken infrequently, in which psychotherapy is not required. Neurological indications include cluster headache, sometimes called “suicide headache”, and other forms of acute and chronic pain, commonly managed with opiate medication leaving the patient unable to function.
Most countries do not have a legalised medical programme for psychedelics yet. In the UK we are calling for the laws to be changed to enable research.
Setbacks of continuing research
Unfortunately, researching psychedelics is particularly difficult as it is extremely costly, bureaucratic and incurs large time delays due to the UN drug control conventions of 1960 and 1971.
In some countries however, significant progress has been made in enabling patient access and research. Psychedelic therapy has been legalised very recently in Oregon, USA. However, most countries do not have a legalised medical programme for psychedelics yet. In the UK we are calling for the laws to be changed to enable research4.
In this rapidly evolving field, we must learn from the mistakes made with medical cannabis5 and ensure that the relevant patient groups receive safe and fair access to psychedelic medicine through the health care systems of that country.
Conflict of Interest
Jo Neill is a scientific advisor to Beckley Psytech, Albert Labs, Psychedelic Experience, Heroic Hearts UK, and the Conservative Drug Policy Reform Group.
 Nutt D, Erritzoe D, Carhart-Harris R. Psychedelic psychiatry’s brave new world. Cell 2020; 181(1): 24-28.
 Carhart-Harris RL, Roseman L, Bolstridge M, Demetriou L, Nienke Pannekoek J, Wall MB, Tanner M, Kaelen M, McGonigle J, Murphy K, Leech R, Curran HV, Nutt DJ. Psilocybin for treatment-resistant depression: fMRI-measured brain mechanisms. Nat Sci Rep 2017: 7(1):131873.
 Morales-Garcia JA, Calleja-Conde J, Lopez-Moreno JA, Alonso-Gil S, Sanz-SanCristobal M, Riba J, Perez-Castillo A. N,N-dimethyltryptamine compound found in the hallucinogenic tea ayahuasca, regulates adult neurogenesis in vitro and in vivo. Transl Psychiatry 2020; 28;10(1):331.
 Rucker J, Schnall J, D’Hotman D, King D, Davis, T, Neill, JC. Medicinal use of psilocybin: reducing restrictions on research and treatment. Report by CDPRG and the Adam Smith Institute 2020 https://www.cdprg.co.uk/psilocybin. (not peer-reviewed).
 Schlag A. An Evaluation of Regulatory Regimes of Medical Cannabis: What Lessons Can Be Learned for the UK? Med Cannabis Cannabinoids 2020;3:76–83.