Journal of Psychopharmacology
September 8, 2010
Tibor M. Brunt, Anneke Poortman, Raymond J.m. Niesink et al.
217 citations
The ecstasy market in the Netherlands became unstable in 2009, with more than a 50% drop in tablets containing MDMA. A new substance, mephedrone, partially replaced MDMA in tablets sold as ecstasy, at doses between 96 and 155 mg. Based on reports from 70 regular ecstasy users, mephedrone produced enjoyable effects similar to other amphetamine-type stimulants, including MDMA, but unlike MDMA it induced strong cravings in most users. If the unstable market continues, mephedrone may substantially substitute for MDMA, raising health concerns.
Clinical toxicology (Philadelphia, Pa.)
January 1, 2016
Ruud P. W. Litjens, Tibor M. Brunt
74 citations
Ibogaine, a psychoactive alkaloid from the African shrub Tabernanthe iboga, is unlicensed but used to treat addiction. It is metabolized mainly by CYP2D6 to noribogaine, which persists for days. Both compounds interact with multiple neurotransmitter systems. In rats, neurotoxicity occurs at doses above 25 mg/kg intraperitoneal, likely via excitotoxic effects on cerebellar Purkinje cells. Cardiotoxicity arises from blockade of hERG potassium channels, prolonging the QT interval and causing arrhythmias and sudden cardiac arrest. Twenty-seven fatalities have been reported; eight case studies show ventricular tachyarrhythmias in individuals without pre-existing heart conditions. Noribogaine appears at least as cardiotoxic as ibogaine. CYP2D6 polymorphism and concurrent medications increase risks. Without medical supervision, further deaths are likely.
Molecular Psychiatry
August 23, 2025
Adam J. Drewko, Ron L. P. Habets, Tibor M. Brunt
4 citations
Serotonergic psychedelics like psilocybin and LSD show promise for treatment-resistant depression by rapidly inducing neuroplasticity, but the molecular mechanisms are debated. This narrative review examines evidence on whether the serotonin 5-HT2A receptor, which mediates hallucinogenic effects, is also required for neuroplasticity. It covers how decreased neuroplasticity relates to depression, how psychedelics promote dendrito-, spino-, and synaptogenesis, and whether these effects are regionally selective. The review critically assesses conflicting studies on the necessity of 5-HT2A signaling for neuroplastic effects and presents a model of the molecular mechanisms involved.