⛔ Dangerous — Avoid Entirely
Lithium is one of the only combinations widely considered an absolute contraindication with psilocybin. Documented case reports link this combination to severe seizures.
Mechanism of Interaction
Lithium is a mood stabilizer prescribed mainly for bipolar disorder. Multiple case reports in the harm-reduction and clinical literature describe severe seizures, including grand mal seizures, in people who combined lithium with psilocybin or other classic psychedelics. The exact pharmacological mechanism is not fully understood, but the pattern across independent reports is consistent enough that harm-reduction organizations (including TripSit) list lithium as a hard "do not combine."
Unlike SSRI interactions, which mostly reduce or block the psychedelic effect, the lithium interaction is a physical safety risk that can occur unpredictably and does not appear to be reliably dose-dependent.
Harm Reduction Guidance
- Do not use psilocybin, in any dose (including microdoses), while taking lithium.
- If you are considering stopping lithium in order to use psilocybin, this must only be done under the direct supervision of your prescribing psychiatrist — abruptly stopping lithium carries its own serious risks (including relapse of the underlying condition).
- Discuss your interest in psychedelics openly with your psychiatrist; some clinicians can advise on alternative mood stabilizers with a different risk profile if psychedelic-assisted therapy is a long-term goal.
- There is no known safe waiting period after stopping lithium that has been established in the literature — any decision to proceed must be made with a physician, not on a fixed timetable found online.
🚑 When to Seek Emergency Help
Seek emergency medical care immediately if seizures, loss of consciousness, confusion, or abnormal muscle movements occur after any combination of lithium and psilocybin. Call your local emergency number (911/999/112) — do not wait to see if symptoms pass.
⚠️ Medical Disclaimer
This page is for educational and harm-reduction purposes only and does not constitute medical advice. Psilocybin remains illegal in most jurisdictions. Always consult a qualified physician or pharmacist before combining any substance with a prescription or over-the-counter medication, especially psychiatric medications, mood stabilizers, or opioids. If you or someone with you develops agitation, confusion, a racing heart, high fever, muscle rigidity, or seizures after combining substances, call emergency services (or your local equivalent of 911/999/112) immediately — these can be signs of serotonin syndrome, a potentially fatal condition.