There is a need for effective, safe new treatments for mental disorders. In the past decade there has been a renewed interest worldwide in psychedelics as potential treatments for various mental health conditions,such as treatment-resistant depression, addictive disorders, post-traumatic stress disorder, and end-of-life psychological distress.
These psychoactive compounds have overlapping effects via different mechanisms of actions which, in the context of therapeutic use, remain to be established.Psychedelic substances induce alterations of consciousness, including visual effects, transient feelings of oneness with the universe, transcendence of time and space, and ego dissolution, but can also induce anxiety and psychological distress, which can be alleviated through interpersonal support during administration.
Classic psychedelics act via 5-HT2A receptor agonism and include mescaline, N,N-dimethyltryptamine, lysergic acid diethylamide, and psilocybin. Atypical psychedelics (eg, 3,4-methylenedioxymethamphetamine and ketamine), have different pharmacological mechanisms of action and also differ in terms of legal status (eg, ketamine and esketamine are approved as medicines in the EU). We do not, therefore, include atypical psychedelics in this discussion of the European regulatory context for potential therapeutic uses of psychedelics in mental disorders. The issues we raise here are informed by our work for the European Medicines Agency (EMA), the EMA’s Central Nervous System Working Party, and the European College of Neuropsychopharmacology (ECNP).