Acute stress disorder (ASD) is an anxiety disorder in which fear and related symptoms are experienced soon after a traumatic event and last less than a month. posttraumatic stress disorder (PTSD) is an anxiety disorder in which fear and related symptoms continue to be experienced long after a traumatic event (Comer, 2010, p. 157).
PTSD vs. ASD
Acute stress disorder (ASD) occurs within four weeks after exposure to traumatic stress and is characterized by dissociative symptoms, reexperiencing of the event, avoidance of reminders of the trauma, and marked anxiety or arousal. Posttraumatic stress disorder (PTSD) also is defined by symptoms of reexperiencing, avoidance, and arousal, but the symptoms either are longer lasting or have a delayed onset.
Comer, R. J. (2010). Abnormal psychology (8th ed.). New York, NY: Worth Publishers.