Beyond the Outburst: Charting a New Frontier for Understanding and Treating Irritability in Autistic Adults.

Irritability is a prevalent and impairing feature associated with autism, yet remains poorly understood, particularly in adults. Drawing heavily on insights translated from pediatric and transdiagnostic literatures, we propose that irritability in autistic individuals often reflects a psychophysiological stress or threat response, rooted in a vulnerable neurobiology (e.g., sensory sensitivities, intolerance of uncertainty), but may also stem from intrinsic neurobiological dysregulation independent of environmental triggers. The current treatment paradigm for autistic adults, largely extrapolated from pediatric antipsychotic trials, leaves these adults critically underserved due to a lack of evidence-based treatments, clinical trials, or validated tools to measure their internal experience. This viewpoint deconstructs irritability, differentiating its affective nature from aggression, and highlights heterogeneity across the lifespan and support needs. We critique the limitations of current assessment methods and recommend a shift toward a multi-modal strategy integrating self-report (when feasible) with objective, physiologically-informed tools (e.g., wearable biosensors) and nuanced observer reports. We argue that the field is poised for neuroscience-informed treatment innovation-including novel pharmacological agents and adapted psychosocial interventions-but is hampered by a lack of rigorous clinical trials in adults. Finally, we call for mechanistically driven trials to address the large unmet burden of inadequately treated irritability, ultimately improving the quality of life for autistic adults and their families/caregivers.