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Acute Stress Disorder (ASD)


John W. Barnhill

, MD, Weill Cornell Medical College and New York Presbyterian Hospital

Last full review/revision October 2018 by John W. Barnhill, MD

Acute stress disorder (ASD) is an intense, unpleasant, and dysfunctional reaction beginning shortly after an overwhelming traumatic event and lasting less than a month. If symptoms persist longer than a month, people are diagnosed as having posttraumatic stress disorder.

(See also Overview of Trauma- and Stress-Related Disorders.)

People with acute stress disorder have been exposed to a terrifying event. They may experience it directly or indirectly. For example, direct exposure may involve experiencing serious injury, violence, or the threat of death. Indirect exposure may involve witnessing events happening to others or learning of events that occurred to close family members or friends. People mentally re-experience the traumatic event, avoid things that remind them of it, and have increased anxiety.

People with this disorder may have dissociative symptoms. For example, they may feel emotionally numb or disconnected from themselves. They may feel that they are not real.

The number of people with acute stress disorder is unknown. The likelihood of developing acute stress disorder is greater when traumatic events are severe or recurrent.


  • A doctor's evaluation, based on specific criteria

Acute stress disorder is diagnosed when people have been

  • Exposed directly or indirectly to a traumatic event

In addition, they also must have had at least 9 of the following symptoms for 3 days up to 1 month:

  • Recurring, uncontrollable, and intrusive distressing memories of the event
  • Recurring distressing dreams of the event
  • Feelings that the traumatic event is recurring—for example, in flashbacks
  • Intense psychologic or physical distress when reminded of the event (for example, by entering a similar location, or by sounds similar to those heard during the event)
  • A persistent inability to experience positive emotions (such as happiness, satisfaction, or loving feelings)
  • An altered sense of reality (for example, feeling in a daze or as if time has slowed)
  • Memory loss for an important part of the traumatic event
  • Efforts to avoid distressing memories, thoughts, or feelings associated with the event
  • Efforts to avoid external reminders (people, places, conversations, activities, objects, and situations) associated with the event
  • Disturbed sleep
  • Irritability or angry outbursts
  • Excessive attention to the possibility of danger (hypervigilance)
  • Difficulty concentrating
  • An exaggerated response to loud noises, sudden movements, or other stimuli (startle response)

In addition, symptoms must cause significant distress or significantly impair functioning.

Doctors also check to see whether symptoms could result from use of a drug or another disorder.


  • Supportive measures

Many people recover from acute stress disorder once they are removed from the traumatic situation and given appropriate support in the form of understanding, empathy for their distress, and an opportunity to describe what happened and their reaction to it. Some people benefit from describing their experience several times. Friends and loved ones can often provide this support. Otherwise, doctors or other health care professionals are helpful.

Sometimes doctors temporarily give drugs to relieve anxiety or help people sleep, but other drugs (such as antidepressants) are usually not given.

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