Psilocybin-assisted therapy (PAT)
A structured clinical protocol in which a controlled dose of psilocybin is administered in a supervised therapeutic setting, paired with psychological preparation before and integration support after. Shorthand: PAT. Distinct from recreational use, microdosing, and from simply "taking psilocybin" — PAT always includes a trained facilitator or therapist, a preparation phase, a supervised dosing session, and structured integration. Currently legal in Oregon (since 2023) and Colorado (since 2025). FDA Breakthrough Therapy designation for treatment-resistant depression and major depressive disorder.
Full Explanation
Psilocybin-assisted therapy (PAT) is a structured clinical protocol in which a controlled dose of psilocybin is administered in a supervised therapeutic setting, paired with psychological preparation before and integration support after. It is also called psilocybin therapy, psilocybin-assisted psychotherapy (PAP), or supported psilocybin therapy. The shorthand PAT is used across clinical and regulatory literature.
PAT has three mandatory phases: 1. Preparation (1–4 weeks, 2–6 meetings) — medical and psychiatric screening, rapport building, intention setting, and review of harm-reduction principles. 2. Dosing session (4–8 hours, usually 1–3 sessions total) — the participant takes psilocybin in a comfortable room with one or two trained guides present and a curated music playlist. 3. Integration (days to weeks after, 2–6+ meetings) — sense-making, processing difficult material, and translating insights into behavior change during the afterglow window.
PAT is distinct from: - Recreational use — no clinical framing, no trained support, no integration. - Microdosing — sub-perceptual doses taken on a schedule for general wellness, not a one-off high-dose clinical intervention. - Simply taking psilocybin — the therapeutic protocol itself (preparation + supervised session + integration) is what clinical trials test, not the drug alone.
PAT has FDA Breakthrough Therapy designation for treatment-resistant depression and major depressive disorder. Phase 3 trials are underway (COMPASS Pathways, Usona Institute). Strong Phase 2 evidence also exists for alcohol use disorder, end-of-life anxiety, and nicotine addiction. Supervised PAT is legal for adults in Oregon (since June 2023) and Colorado (since June 2025).
See: Psilocybin Therapy (/guides/psilocybin-therapy), Integration (/glossary/integration), Set and Setting (/glossary/set-and-setting).
Why It Matters
Using PAT rather than "psilocybin" in discussion and content is how the clinical and regulatory world talks about this treatment. It also makes the distinction between supervised clinical use and recreational use unambiguous — which matters for legal, insurance, and safety reasons.
Related Guides
Explore More Terms
Psilocybin
A naturally occurring psychedelic compound found in certain mushrooms that produces altered states of consciousness.
Psilocin
The pharmacologically active compound that psilocybin converts to in the body, responsible for psychedelic effects.
Ego Death
A temporary dissolution of the sense of self during a psychedelic experience, often described as profound and transformative.
Set and Setting
The combination of mindset (set) and environment (setting) that shapes a psychedelic experience.
Microdosing
Taking sub-perceptual doses of psilocybin on a regular schedule for subtle cognitive and emotional benefits.
Mycelium
The vegetative part of a fungus, consisting of a network of fine white filaments that eventually produces mushrooms.