Post-traumatic stress disorder (PTSD) is an anxiety disorder caused by very stressful, frightening or distressing events.

Someone with PTSD often relives the traumatic event through nightmares and flashbacks, and may experience feelings of isolation, irritability and guilt. They may also have problems sleeping, such as insomnia, and find concentrating difficult.

These symptoms are often severe and persistent enough to have a significant impact on the person’s day-to-day life.