How toxic is ibogaine?
Level 5 - mechanism / opinion, no new human data
Narrative literature review synthesizing mechanistic, animal, and human case report data without systematic trial evaluation.
PubMed 26807959 · doi:10.3109/15563650.2016.1138226
What was done
The authors conducted a narrative literature review via a PubMed search on ibogaine and noribogaine using predefined keywords covering pharmacokinetics, pharmacodynamics, mechanism of action, and toxicology. The search identified 382 unique references (156 with human data), including 14 detailed toxicological case reports that were qualitatively analyzed.
What was found
Ibogaine is metabolized by CYP2D6 into noribogaine, which persists at clinically relevant concentrations for days. Both agents show micromolar affinity for NMDA, kappa-, and mu-opioid receptors, and sigma-2 sites. Neurotoxicity with Purkinje cell loss was demonstrated in rats at intra-peritoneal doses exceeding 25 mg/kg. Cardiotoxicity occurs via hERG potassium channel blockade, leading to delayed cardiac repolarization and QT prolongation. The review identified 27 published fatalities following ibogaine ingestion (often with pre-existing cardiovascular disease) and 8 case reports of QT prolongation and ventricular tachyarrhythmias occurring in individuals without pre-existing cardiac disease or family history.
Why it matters
Unregulated ibogaine administration presents substantial, potentially fatal cardiotoxic risks that persist for days post-ingestion due to active metabolite kinetics and hERG channel inhibition.
Limits
The abstract describes a narrative search rather than a formal systematic review or meta-analysis. Findings rely primarily on preclinical animal experiments and uncontrolled, spontaneous adverse event case reports, which cannot establish true incidence rates or human dose-response thresholds.