Find information on medical topics, symptoms, drugs, procedures, news and more, written in everyday language.

* This is the Consumer Version. *

Posttraumatic Stress Disorder (PTSD)

by John H. Greist, MD

Posttraumatic stress disorder (PTSD) is characterized by recurrent, intrusive recollections of an overwhelming traumatic event.

  • Events that threaten death or serious injury can cause intense, long-lasting distress.

  • Affected people may relive the event, have nightmares, and avoid anything that reminds them of the event.

  • Treatment may include psychotherapy (supportive and exposure therapy) and antidepressants.

Experiencing or witnessing traumatic events that threaten death or serious injury can affect people long after the experience is over. Intense fear, helplessness, or horror experienced during the traumatic event can haunt them.

Events that can lead to posttraumatic stress disorder include the following:

  • Engaging in combat

  • Experiencing or witnessing sexual or physical assault

  • Experiencing a disaster, either natural (for example, a hurricane) or man-made (for example, a severe automobile accident)

Sometimes symptoms do not begin until many months or even years after the traumatic event took place. If posttraumatic stress disorder has been present for 3 months or longer, it is considered chronic.

Posttraumatic stress disorder affects almost 8% of people sometime during their life, including childhood (see Acute and Posttraumatic Stress Disorders in Children and Adolescents). Many people who undergo or witness traumatic events, such as combat veterans and victims of rape or other violent acts, experience posttraumatic stress disorder.


In posttraumatic stress disorder, people have frequent, unwanted memories replaying the traumatic event. Nightmares are common. Much less often, people relive events as if they were actually happening (flashbacks) rather than simply being remembered.

Intense distress often occurs when people are exposed to an event or situation that reminds them of the original trauma. Examples of such reminders are anniversaries of the traumatic event, seeing a gun after being pistol-whipped during a robbery, and being in a small boat after a near-drowning accident.

People persistently avoid things—activities, situations, or people—that are reminders of the trauma. For example, they may avoid entering a park or an office building where they were assaulted or avoid speaking to people of the same race as their assailant. They may even attempt to avoid thoughts, feelings, or conversations about the traumatic event. Avoidance may also include memory loss (amnesia) for a particular aspect of the traumatic event.

People have a numbing or deadening of emotional responsiveness and have symptoms of increased arousal (such as difficulty falling asleep, being vigilant for warning signs of risk, or being easily startled). Symptoms of depression are common, and people show less interest in previously enjoyed activities. Feelings of guilt are also common. For example, they may feel guilty that they survived when other people did not. Some people develop ritual activities to help reduce their anxiety. For example, people who were sexually assaulted may bathe repeatedly to try to remove the sense of being unclean.


Treatment involves psychotherapy (particularly exposure therapy) and drug therapy.

In exposure therapy, the therapist has people imagine being in situations or with people that they avoid because they associate these situations and people with the trauma. For example, they may be asked to imagine visiting a park where they were assaulted. The therapist also helps people reimagine the traumatic event itself. Because of the often intense anxiety associated with traumatic memories, supportive psychotherapy plays an especially important role in treatment. The therapist is openly empathic and sympathetic in recognizing the psychologic pain. The therapist reassures people that their response is valid but encourages them to face their memories (as a form of exposure therapy). They are also taught ways to control anxiety, which help modulate and integrate the painful memories into their personality. Exposure therapy also includes preventing people from performing any of the rituals they have developed.

Eye movement desensitization and reprocessing (EMDR) is a form of exposure therapy. In EMDR, people follow the therapist's moving finger with their eyes while imagining being exposed to the trauma. Some experts think that the eye movements themselves help with desensitization, but EMDR probably works mainly because of the exposure, not the eye movements.

Antidepressants, particularly selective serotonin reuptake inhibitors (SSRIs), are especially helpful. Prazosin (also used to treat high blood pressure) may help reduce the number of nightmares. Many other drugs, including drugs that stabilize mood (such as valproate) or treat psychotic disorders, have been tried, but whether they are effective is unclear.

Chronic posttraumatic stress disorder may not disappear but often becomes less intense over time even without treatment. Nevertheless, some people remain severely handicapped by the disorder.

Drugs Mentioned In This Article

  • Generic Name
    Select Brand Names