252. Clinical application of psychedelic-assisted therapy in major depression and addictions

Abstract

Abstract Background Recent clinical and neuroscientific work has revived interest in psychedelic-assisted therapies as promising treatments for a range of psychiatric conditions. Mechanistically, classical psychedelics and atypical agents such as ketamine appear to act as catalysts of neural and psychological flexibility, disrupting entrenched patterns of activity in “stuck” brain networks and creating windows for relearning and psychotherapeutic change. Over the last decade, randomized and open-label trials, pooled analyses, and mechanistic studies have reported clinically meaningful effects for major depressive disorder (including treatment-resistant cases), certain substance use disorders, and some eating disorders, alongside growing data on safety, dosing paradigms, and the importance of psychosocial support. Aims & Objectives - To synthesize current psychological and neurobiological models explaining how psychedelic interventions facilitate therapeutic change. - To summarize the principal clinical trial findings, with focus on depression data - To explore practical strategies for integrating psychedelic therapies into existing healthcare frameworks, with an emphasis on scalable, equitable, and evidence-generating approaches. - To use emerging ketamine service pilots in the UK NHS as a worked example. Method Outlined above. Results - Mechanistic insights: Neuroimaging and neurophysiological studies show that psychedelic compounds can transiently reduce rigidity in large-scale brain networks (e.g., default mode network), increase connectivity and entropy measures, and enhance plasticity-related signaling, correlating with reported increases in cognitive and emotional flexibility. - Clinical efficacy: Trials in depression overall report significant, often rapid reductions in depressive symptoms after single or limited dosing sessions (including ketamine’s rapid antidepressant effects and longer-term benefits reported with psilocybin plus psychotherapy). Early-stage trials for some substance use disorders and eating disorders demonstrate promising remission and relapse-prevention signals, though sample sizes and follow-up durations vary. Discussion & Conclusions Service models and pilots and national strategy, incl discussion of new commission set up to develop strategy for safe implementation of psychedelic therapy in the UK.