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acute danger to life

Serotonin Syndrome

When When tremor, muscle twitching, hyperthermia, confusion, diarrhea, or seizures occur after using serotonergic substances (MDMA, MDA, MAOI, SSRI/SNRI, DXM, tramadol) — often in combination.

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Content is undergoing medical and legal review. Changes possible.

Emergency

Call 112. Calling for help is required by law (German Criminal Code § 323c). levelll cannot promise immunity from criminal or administrative consequences.

Immediate

  1. 1. Call 112 — the course can become life-threatening within hours.
  2. 2. Actively cool the person if body temperature is elevated (cold cloths on armpits, groin, neck).
  3. 3. Position them calmly, reduce stimulation. Monitor breathing.

Don't do

  • Do not give any more serotonergic substances — it worsens the syndrome.
  • Do not let them drink a lot of water at once — risk of hyponatremia (see separate scenario).
  • No self-medication with antihistamines or sedatives — interactions are unpredictable.

Serotonin syndrome is caused by an excess of serotonin in the central nervous system — usually through the combination of two serotonergic substances. Most common triggers:

  • MDMA + MAOI (hartrot, classically fatal) — moclobemide, selegiline, some ayahuasca admixtures
  • MDMA + SSRI/SNRI (antidepressants: citalopram, sertraline, venlafaxine, etc.)
  • MDMA + DXM (in cough medicines)
  • Tramadol + SSRI (clinically documented)

Symptom triad, Hunter criteria:

  1. Neuromuscular: clonus, tremor, hyperreflexia
  2. Autonomic: hyperthermia, tachycardia, sweating
  3. Mental: agitation, confusion, seizures

Clinical care includes cyproheptadine and intensive symptom control. In an acute emergency, calling 112 is the only sensible action for a layperson.

If you take antidepressants (SSRI/SNRI): MDMA use is not safely controllable, not even at “just small” doses. A complete washout period after an SSRI takes 1–6 weeks depending on the active ingredient.