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Psilocybin, in 10mg or 25mg doses, has no detrimental effects in healthy people

New research has shown that psilocybin, a psychedelic drug isolated from the Psilocybe mushroom, can be safely administered at doses of either 10mg or 25mg to up to six participants at the same time. 

The study, supported by NIHR, was led by researchers from King's College London in partnership with COMPASS Pathways and published in the Journal of Psychopharmacology

This is the first time that a study of this scale (89 participants) on psilocybin has been published in a peer-reviewed journal. Early research has indicated a potential for psilocybin therapy to treat mental health conditions, but no trials have been undertaken at the scale needed for regulatory approval to make the therapy available.

A potential new treatment

The research is an essential first step in demonstrating the safety and feasibility of psilocybin for use within controlled settings alongside talking therapy as a potential treatment for a range of mental health conditions. These include treatment-resistant depression (TRD) and post-traumatic stress disorder (PTSD). Current treatment options for these conditions are ineffective or partially effective for many people, resulting in a significant unmet need. 

The trial is the first of its kind to thoroughly investigate the simultaneous administration of psilocybin. 89 healthy participants with no recent use of psilocybin were recruited. 60 individuals were randomly picked to receive either a 10mg or 25mg dose of psilocybin in a controlled environment.

All participants were provided with one-to-one support from trained psychotherapists. The remaining 29 participants acted as the control group and received a placebo, also with psychological support.

NIHR Clinical Scientist Dr James Rucker, the study’s lead author from King's College London and honorary consultant psychiatrist at South London and Maudsley NHS Foundation Trust said:

“This rigorous study is an important first demonstration that the simultaneous administration of psilocybin can be explored further. If we think about how psilocybin therapy (if approved) may be delivered in the future, it's important to demonstrate the feasibility and the safety of giving it to more than one person at the same time, so we can think about how we scale up the treatment.

“This therapy has promise for people living with serious mental health problems, like treatment-resistant depression (TRD) and PTSD. They can be extremely disabling, distressing and disruptive, but current treatment options for these conditions are ineffective or partially effective for many people.”

The trial was supported by the NIHR Maudsley Biomedical Research Centre (BRC) and took place in the NIHR King’s Clinical Research Facility (CRF)

Read more about this research on the NIHR Maudsley BRC website