Posttraumatic stress disorder (PTSD) may develop after a person is exposed to one or more traumatic events, such as sexual assault, warfare, serious injury, natural disaster, bushfire, flood, or threats of imminent death. The diagnosis may be given when a group of symptoms, such as disturbing recurring flashbacks, avoidance or numbing of memories of the event, and hyper-arousal, continue for more than a month after the occurrence of a traumatic event. People with PTSD often experience feelings of panic or extreme fear, which may resemble what was felt during the traumatic event.
Up to 80% of people who have long-standing PTSD develop additional problems, most commonly depression, anxiety and alcohol or other substance misuse. These may have developed directly in response to the traumatic event or have developed sometime later after the onset of PTSD.