Posttraumatic stress disorder (PTSD), once called shell shock or battle fatigue syndrome, is a serious condition that can develop after a person has experienced or witnessed a traumatic or terrifying event in which serious physical harm occurred or was threatened. PTSD is a lasting consequence of traumatic ordeals that cause intense fear, helplessness, or horror, such as a sexual or physical assault, the unexpected death of a loved one, an accident, war, or natural disaster. Families of victims can also develop PTSD, as can emergency personnel and rescue workers.
Most people who experience a traumatic event will have reactions that may include shock, anger, nervousness, fear, and even guilt. These reactions are common; and for most people, they go away over time. For a person with PTSD, however, these feelings continue and even increase, becoming so strong that they keep the person from living a normal life. People with PTSD have symptoms for longer than one month and cannot function as well as before the event occurred.
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