This factsheet is also available as a pdf.
PTSD is a psychiatric disorder which usually develops following exposure to one of a range of distressing experiences including actual or threatened death, serious injury or sexual violence. While usually diagnosed following a traumatic experience in some cases PTSD can develop months or occasionally years later, though a delay in seeking help is more common than true delayed onset.
There are distinct sets of symptoms for PTSD: re-experiencing the traumatic experience through flashbacks, nightmares or repetitive thoughts; persistent avoidance of situations that trigger memories of the experience; and altered states of arousal or reactivity like being irritable, aggressive or hypervigilant, and having poor concentration and disturbed sleep. PTSD sufferers also have negative changes to their cognitions and mood like feeling angry, guilty or shameful and often lose interest in activities and become alienated from others. The condition often occurs alongside other psychiatric disorders such as depression or substance misuse.
Short-lived distress symptoms are common after a traumatic event and should not be seen as requiring treatment. A diagnosis of PTSD is made if symptoms last several weeks, remain severe and significantly impact day-to-day life. There are no physical tests, so PTSD is diagnosed via a detailed psychological assessment.
Most people who experience a trauma do not develop PTSD and it is not wholly clear why some do. Some traumas, such as sexual assault, are associated with higher rates, and trained emergency or military personnel are less likely to develop PTSD than civilians exposed to similar incidents. Large population studies in the US and Europe suggest around 7% of people develop PTSD over their lifetime but prevalence can vary widely between high risk groups. PTSD is more common in women and adults and amongst those with prior mental illness. Although no one factor can predict the development of PTSD, perceived level of social support has been shown to have the most influence.
Trauma-Focused Cognitive Behavioural Therapy (TF-CBT), tailored towards confronting the trauma, and another psychological treatment called Eye Movement Desensitisation and Reprocessing (EMDR) are shown to be effective treatments. Antidepressant medication can also be used, especially when the talking therapies are ineffective or unavailable. Some therapies that are claimed to be effective, such as Neurolinguistic Programming (NLP), have no evidence to justify their use.
NHS Choices information page
Mental Health Foundation information page
This is a fact sheet issued by the Science Media Centre to provide background information on science topics relevant to breaking news stories. This is not intended as the ‘last word’ on a subject, but rather a summary of the basics and a pointer towards sources of more detailed information. These can be read as supplements to our roundups and/or briefings.