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Psilocybin-assisted therapy

A course of psychotherapy built around one or more supervised psilocybin sessions, with preparation before and integration after. This reading is for someone who wonders whether it could help them.

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Psilocybin-assisted therapy

  • Prepare — Needs and expectations
  • Experience — Supervision and support
  • Integrate — Meaning and next steps

Structured support around a substance session. Session numbers and timing vary.

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What is psilocybin?

Psilocybin is the active compound of certain mushrooms. In the body it becomes psilocin, which acts on the brain's serotonin receptors. Within an hour of taking it, perception, emotion, the sense of time and the sense of self begin to change; the effects last four to six hours. In therapy, the psilocybin is a standardised preparation of known dose, taken once or a few times, each time with a trained person present. 1

Therapy or recreation?

The substance is the same; the frame is not. Recreational use seeks the experience itself, usually with others, with whatever mushrooms are at hand and no one to turn to if things go badly. Therapeutic use starts from a difficulty you want to address. The dose is known, the setting is quiet and protected, the person beside you has prepared you and will stay to the end, and the weeks after are given to working with what came up. This is why a difficult moment that would be a bad trip in one setting can become, in the other, the heart of the work.

What does the process look like?

Preparation comes first, over several meetings: what brings you, your history and your health, what you hope for and what you fear, and how the session will be held. This is where consent is worked out in detail, including how you will be supported if the experience becomes difficult and how you can stop at any point. The session itself lasts a day. You lie down, often with eye shades and music, and turn inward; the therapist is there throughout and intervenes little unless you need them. Experiences of openness, closeness or release can alternate with fear, grief or confusion within the same hours. Integration follows over the following weeks: meetings to look at what surfaced and at what it changes in your life. A course may involve one session or several; there is no fixed number. 1

What is it used for?

Psilocybin-assisted therapy is being used, within research and exceptional-access settings, for depression that has not responded to other treatments, for the anxiety and depression that accompany a life-threatening illness, and for alcohol dependence. People who seek it usually have tried other forms of help first. It is not a treatment for every difficulty, and it is not a shortcut; the therapy around the session is where most of the work is done. 2–4

Adverse effects

During the session, nausea, headache, a faster heartbeat and a rise in blood pressure are common and pass with the effects. Anxiety and panic can occur, particularly at the height of the experience; with preparation and someone present, they are usually workable and often meaningful. Some people relive fragments of the experience in the following days or weeks. Rarely, a person with a predisposition may be tipped into a lasting psychiatric disturbance; this is the main reason for careful screening beforehand. 1

Who should not do this?

A personal or family history of psychosis or bipolar disorder, an unstable heart condition or high blood pressure, and certain current medications, in particular some antidepressants, call for caution or rule the approach out. So does a period of acute crisis. These are not a checklist to apply to yourself: they are discussed with the clinician, and any change to a medication is agreed with the prescriber. 1

Where things stand in Canada

Psilocybin is not an approved treatment in Canada; the mushrooms themselves are illegal to produce, sell or possess. Access exists through authorised clinical trials and, for some people, through Health Canada's Special Access Program, requested by a regulated practitioner, case by case. Neither route establishes general availability or your eligibility. A consultation with a qualified clinician is the place to find out what applies to you; support without a substance is available in the meantime (see Psychedelic harm reduction and integration). 1

Questions to bring to a consultation

  • Given what I wish to address, what is the best way forward?
  • Is this approach suited to my situation, my health and the treatments I take?
  • Who will be with me during the session, and what is their training?
  • How are difficult moments and physical effects handled?
  • What does the integration work look like afterwards?
  • What are the alternatives?

Sources and further reading

  1. Health Canada / Santé Canada · Psilocybin and psilocin (magic mushrooms). Effects, risks and Canadian access pathways; French version available.
  2. Goodwin et al. (2022) · Single-dose psilocybin for a treatment-resistant episode of major depression. New England Journal of Medicine. doi 10.1056/NEJMoa2206443
  3. Griffiths et al. (2016) · Psilocybin in patients with life-threatening cancer. Journal of Psychopharmacology. doi 10.1177/0269881116675513
  4. Bogenschutz et al. (2022) · Psilocybin-assisted psychotherapy in alcohol use disorder. JAMA Psychiatry. doi 10.1001/jamapsychiatry.2022.2096

General information to support a clinical conversation. This resource does not determine treatment suitability or offer access to a substance.

Questions about working together? Begin a conversation.

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