As you may know, I just finished an intense course of study to become certified as a Psychedelic Assisted Therapist. Since completing that work, I’ve connected with quite a few other therapists and guides engaging in this kind of work, and I have integrated these ideas into my clinical practice. I believe in the healing potential of these medicines, and their positive impact on brain neuroplasticity.
But what are the differences?
Psilocybin therapy and ketamine therapy are both forms of psychedelic-assisted treatment used primarily for mental health conditions like depression, PTSD, and anxiety. However, they differ significantly in terms of their mechanisms of action, experience, legal/regulatory status, and clinical use.
Here’s a breakdown of the key differences:
1. Substance and Mechanism of Action
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Psilocybin:
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Derived from: Psilocybin mushrooms (“magic mushrooms”).
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Mechanism: Serotonergic psychedelic – primarily activates 5-HT2A serotonin receptors.
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Effect: Profound alterations in perception, sense of self, and cognition, often leading to mystical or spiritual experiences.
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Ketamine:
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Originally used as: An anesthetic.
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Mechanism: NMDA receptor antagonist; also affects glutamate and opioid systems.
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Effect: Dissociative experiences, often described as feeling “detached” from body or surroundings, but usually less “visionary” than psilocybin.
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2. Therapeutic Use and Frequency
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Psilocybin Therapy:
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Usually involves 1–3 guided sessions, with preparation and integration therapy.
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Long-lasting benefits after just one or two doses have been reported in clinical trials.
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Therapy sessions last 6–8 hours, often with eyeshades and music, under supervision.
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Ketamine Therapy:
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Typically involves a series of infusions or doses (e.g., 6–12 over several weeks), with booster sessions as needed.
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Effects last a few days to a few weeks, so ongoing treatment is often necessary.
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Sessions last about 1–2 hours, sometimes combined with psychotherapy.
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3. Subjective Experience
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Psilocybin:
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Deeply introspective, often involves strong emotions, visual and auditory hallucinations.
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Frequently described as mystical, spiritual, or life-changing.
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Ketamine:
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More of a dissociative state, sometimes dreamlike or abstract.
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Less emotional depth or personal insight for some patients (but varies).
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4. Legal and Regulatory Status
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Psilocybin:
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Still classified as a Schedule I drug in the U.S. (illegal federally).
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Legal for therapy in Oregon and Colorado under state programs; in clinical trials elsewhere.
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Gaining traction for FDA approval as a treatment for major depression.
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Ketamine:
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FDA-approved (as a general anesthetic and for depression in the form of Spravato [esketamine]).
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Legally prescribed “off-label” for depression, PTSD, anxiety, etc.
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5. Clinical Evidence
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Psilocybin:
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Strong evidence for treatment-resistant depression, end-of-life anxiety, and addiction.
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Long-lasting improvements in mood and well-being after few doses.
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Ketamine:
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Rapid reduction in suicidal ideation and depressive symptoms.
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Especially effective for acute intervention, but may require ongoing use.
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| Feature | Psilocybin | Ketamine |
|---|---|---|
| Type | Classic psychedelic | Dissociative anesthetic |
| Main receptor | 5-HT2A (serotonin) | NMDA (glutamate) |
| Duration | 6–8 hours | 45–90 minutes |
| Frequency | 1–3 sessions (long-term impact) | Multiple sessions, often ongoing |
| Experience | Mystical, introspective | Dissociative, dreamlike |
| FDA status (U.S.) | Investigational (some state-legal) | Approved (Spravato) / Off-label use |
| Integration therapy | Strongly emphasized | Often used but not always required |
If you think you are interested in either, let’s chat. We are conducting a 1-day Ketamine retreat later this year – this a great way to learn about Ketamine, use it in a safe and therapeutic environment, and reap the benefits of it’s healing power.
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