Acute stress disorder (ASD) is a short-term psychiatric condition that develops within days of exposure to a traumatic or life-threatening event. ASD is characterized by intrusive memories, dissociation, avoidance, hyperarousal, and functional impairment lasting from 3 days to 1 month after trauma exposure. Early recognition is critical because untreated ASD may progress to posttraumatic stress disorder (PTSD). Symptoms persisting beyond 1 month suggest PTSD when diagnostic criteria are met. Diagnosing acute stress disorder facilitates the early identification of severe posttraumatic distress that might otherwise be overlooked or inaccurately diagnosed as an adjustment disorder.

Acute stress disorder was first introduced in the Diagnostic and Statistical Manual of Mental Disorders, 4th Edition (DSM-IV) in 1994 as a distinct diagnosis to describe acute stress reactions following trauma exposure. The classification aimed to enhance care for trauma survivors and help identify individuals at increased risk for PTSD, allowing timely intervention and prevention efforts. The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5), later reclassified ASD under trauma- and stressor-related disorders and removed the requirement for dissociative symptoms as a diagnostic criterion, reflecting an improved understanding of trauma responses. The Diagnostic and Statistical Manual of Mental Disorders, 5th Edition, Text Revision (DSM-5-TR), retained the same core diagnostic framework. Understanding the epidemiology, pathophysiology, diagnostic framework, and treatment of ASD enables clinicians to deliver timely, evidence-based, and trauma-informed care that promotes recovery and resilience.