Recruitment for an upcoming trial - PsilOCD

Key information


Strict criteria apply for participating in our trials
We receive a high volume of applications - for more information on eligibility and to apply for a telephone screening.


Contact the study team: psilocd@imperial.ac.uk. Please only contact this email address with queries related to the PsilOCD study.
For all other enquiries please email psychedelicresearch@imperial.ac.uk.

Obsessive Compulsive Disorder (OCD) is a costly, distressing disorder and a leading global cause of functional disability. OCD is a heritable lifespan disorders that is defined by the irresistible urge to perform distressing and time-consuming compulsive acts. Development of new treatments is needed to improve health outcomes in those with OCD. Increasing our understanding of OCD would be expected to have wider implications for understanding other obsessive-compulsive related disorders, as well as the broader family of disorders of compulsivity such as eating disorders and substance and behavioural addictions.

For this study, we are recruiting adults with OCD who meet our study criteria (see below). Those who are deemed eligible at screening will attend fifteen study visits (3 face-to-face) over 10 weeks. Participants will receive psilocybin twice, with a dose up to 10mg. Across these fifteen visits, there will be two electroencephalogram (EEG) recordings, and a range of questionnaires and interviews. 

The inclusion criteria are:

Key Inclusion Criteria:

  • Aged 20 to 65 years
  • Any gender
  • A primary diagnosis of OCD DSM-IV or ICD-10 (MINI-5)
  • Score ≥ 16 on Y-BOCS
  • Suffered from OCD for at least 12 months, patient history
  • Not currently depressed with a score of ≤ 24 on MADRS
  • Willing to comply with protocol and lifestyle restrictions
  • Being able to identify a trusted person who the patient would be willing to reach out to in case of need.
  • Excellent understanding of English (for questionnaires)
  • Participant is ambulant and capable of attending a visit as an outpatient.
  • Comfortable using a computer, access to internet from home and willing to have some of the study visits via video-link.

Key Exclusion Criteria:

  • Current or past history of dependent (according to ICD10 criteria] substance use [not including nicotine and/or caffeine), Tourette’s syndrome, autism spectrum disorder, epilepsy, organic mental disorder, personality disorder apart from obsessive compulsive personality disorder.
  • Current or past history of psychosis or mania in themselves or a first degree relative
  • Had a previous severe adverse effect after psychedelic use
  • Specific medication for OCD other than SSRIs (e.g. antipsychotics, clomipramine and glutamatergic drugs taken ‘off-label’ for OCD)
  • History of psychosurgery
  • History of serious suicide attempts requiring hospitalisation
  • Current or chronic history of kidney or liver disease, and/or biochemistry renal/hepatic derangement of clinical significance, as determined by study clinician
  • In the opinion of the study team they are unlikely to comply with the study protocol and lifestyle restrictions that it imposes
  • Unstable physical illness
  • Significantly abnormal clinical test result
  • Significant cardiovascular disease
  • Patients presenting with arrhythmias or abnormal QT interval prolongation at screening or with a history of this (QTc at screening above 440ms for men and above 470ms for women)
  • Heavy smoker, or unable to complete the dosing and recovery part of the study visit without a smoking break
  • Those needing regular specified medication that might interact adversely with psilocybin e.g. 5HT1 agonists, mirtazapine, trazodone, analgesics that have serotonergic effects (tramadol), MAOI’s, antipsychotics with significant 5-HT2A receptor antagonist actions (risperidone, olanzapine and quetiapine)
  • Those judged to have inadequate understanding of English to participate in treatment or give informed consent;
  • Those unwilling to allow their GP or involved mental health practitioners to be informed of their participation, or allow study team access to Summary Care Record
  • Women of child-bearing age who are not using reliable contraceptive methods (see below)
  • Women of childbearing age who are unable to comply with or produce a positive pregnancy urine test.

Please note that Psilocybin is not a licenced drug or treatment for OCD and therefore cannot be prescribed outside specific timepoints during this study regardless of any positive outcomes. For more information and to register your interest visit apply for a remote video screening.

For any questions, please contact the study team on: psilocd@imperial.ac.uk. Please only contact this email address with queries related to the OCD study. For all other enquiries please email psychedelicresearch@imperial.ac.uk.