Psilocybin for OCD

Could psilocybin be used to treat OCD?

Psilocybin is currently being researched as a treatment for OCD by Drug Science founder, Prof David Nutt, at the Centre for Psychedelic Research. In this Drug Science webinar, Dr Nick Sireau provides an overview of OCD and the new research being launched into psilocybin as a potential treatment.

OCD affects 2-3% of the population (up to 1.5 million people in the UK), and the WHO has classified it as one of the 10 leading causes of disability worldwide. Unfortunately, 40-50% of OCD patients will not respond to current treatments. In fact, most current medications take 2-3 months to have any effect and are normally prescribed alongside antipsychotic drugs. Despite this, OCD is the least funded of all mental health disorders.

Dr Sireau describes the obsessions and compulsions that characterise OCD, including the difference between types of OCD such as:

  • Contamination-based OCD in which people have an overriding phobia of contamination.
  • Pure OCD, where the obsessions and compulsions are entirely mental, such as the fear of harming people if they lose control.
  • False memory OCD, in which a false memory is fabricated and then plagues the person, despite being entirely fictional.

He then outlines the design of the first UK trial of psilocybin for OCD, which will assess 20 patients, who will receive 2 sessions of psilocybin therapy and will be investigated with the YBOCS OCD test and a variety of other technical measures. The study was funded by Orchard, a charity set up by Dr Sireau to fund research into new OCD treatments such as psilocybin therapy.

Dr Sireau also explains the other research into psilocybin for OCD which is taking place at research centres around the world.


This webinar was recorded during the Student Psychedelic Conference and included a live Q&A session from the audience. If you want to ensure that you don’t miss any of our events, so that you can ask your questions live, all you need to do is join the Drug Science Mailing List.

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