Post-traumatic stress disorder

Post-traumatic stress disorder (PTSD) is a psychological and physical condition that is caused by very frightening or distressing events. It occurs in up to 30% of people who experience traumatic events.

Traumatic events

PTSD can occur after experiencing or witnessing traumatic events such as:

  • military combat,
  • serious road accidents,
  • terrorist attacks,
  • natural or man-made disasters,
  • being held hostage,
  • violent deaths, and
  • violent personal assaults, such as sexual assault, mugging or robbery.

PTSD may also occur in any other situation where a person feels extreme fear, horror or helplessness. However, it does not usually develop after situations that are upsetting, such as divorces, job losses or failing exams.

Someone with PTSD often relives the traumatic event through nightmares and flashbacks. They may also have problems concentrating and sleeping, and feel isolated and detached. These symptoms are often persistent and severe enough to have a significant impact on a person's day-to-day life.

PTSD is a mental health condition

PTSD first came to prominence during the First World War after soldiers suffered harrowing experiences in the trenches. Their condition became known as shell shock or battle fatigue syndrome. It has not been until fairly recently that it has been accepted that traumatic events outside of war situations have similar effects.

The term 'post-traumatic stress disorder' was first used after the Vietnam War. In 1980, PTSD officially became recognised as a mental health condition when it was included in the Diagnostic and Statistical Manual of Mental Disorders, which was developed by the American Psychiatric Association (APA).

How common is PTSD?

PTSD affects up to 30% of people who experience a traumatic event. It affects around 5% of men and 10% of women at some point during their life, and can occur at any age, including during childhood.

Approximately 40% of people with PTSD develop the condition after someone close to them suddenly dies.


PTSD can be successfully treated even when it occurs many years after the traumatic event. Depending on the severity of your symptoms, and how soon they develop after the traumatic event, a number of different treatment strategies may be recommended. These include:

  • watchful waiting: waiting to see if the symptoms improve or get worse without treatment,
  • psychological treatment, such as trauma-focused cognitive behavioural therapy (CBT), or eye movement desensitisation and reprocessing (EDMR), and
  • medication, such as paroxetine or mirtazapine.

See Treatment for more information about the recommended treatments for PTSD.

The symptoms of post-traumatic stress disorder (PTSD) usually develop immediately after the traumatic event. However, in some cases (less than 15%), the onset of symptoms may be delayed for weeks, months or years.

In PTSD, there are often periods of time when symptoms are reduced (symptom remission). These are followed by periods when symptoms increase. Some people with PTSD have symptoms that are severe and constant.

Most people who witness a traumatic event experience some of the symptoms of PTSD. The nature and severity of symptoms can vary widely between individuals. Some of the main symptoms associated with PTSD are described below.


If you have PTSD, you may frequently relive the traumatic event in the form of flashbacks, nightmares, or repetitive and distressing images or sensations. However, some aspects of the traumatic event may be forgotten in time.


Constantly reliving a traumatic experience can be very upsetting. If you have PTSD, you may try to avoid circumstances, situations or people that remind you of the traumatic event. You may also refuse to discuss your experience with others.


If you have PTSD, you may find it very difficult to relax, and you may be anxious all the time. You may be hypervigilant (constantly aware) to threats, and be easily startled.

Irritability and angry outbursts are also common symptoms of PTSD. You may have sleeping problems, and find it difficult to concentrate.

Emotional numbing

Sometimes, people with PTSD deal with their feelings by trying not to feel anything at all. This is known as 'emotional numbing'.

If you have PTSD, you may feel detached or isolated from others. You may also experience feelings of guilt.

People with PTSD often seem deep in thought (introspective) and withdrawn. They may give up activities and pastimes that they used to enjoy.

Other symptoms

Other common symptoms of PTSD include:

  • depression, anxiety and phobias,
  • drug or alcohol misuse, and
  • unexplained physical symptoms, such as sweating, shaking, headaches, dizziness, chest pains and stomach upsets.

As with many mental health conditions, PTSD sometimes leads to the breakdown of relationships, and causes problems at work.

PTSD in Children

PTSD sometimes affects children who have witnessed a traumatic event, such as a road traffic accident. They may repeatedly re-enact the traumatic event through play, and they may have frightening and upsetting dreams.

Like adults, children with PTSD may lose interest in activities that they used to enjoy. They may also experience headaches and stomach aches.

It is not fully understood why some people develop post-traumatic stress disorder (PTSD) after experiencing a traumatic event, while others do not. However, there are a number of risk factors that seem to make certain people more likely to develop the condition.

Risk factors

If you have had depression or anxiety in the past, or you do not receive much support from family or friends, you are more susceptible to PTSD.

There may also be a genetic factor involved in PTSD. For example, it is thought that having a parent with a mental health problem increases your chances of developing the condition.

Being abused during childhood is thought to be another risk factor for PTSD.

Abnormal hormone response

Studies have shown that people with PTSD have abnormal levels of stress hormones.

When you are in danger, your body produces a number of natural chemicals, such as adrenalin. In very stressful situations, adrenalin triggers a reaction in the body, which is often referred to as the 'fight or flight' reaction. Adrenalin helps to deaden the senses and dulls pain.

People with PTSD have been found to continue to produce high amounts of 'fight or flight' hormones even when there is no danger. This may be responsible for their numbed emotions and feelings of detachment.

The hippocampus

The hippocampus is the part of the brain that is responsible for memory and emotions. In people with PTSD, the hippocampus appears different in MRI (magnetic resonance imaging) scans. It is thought that the changes to the hippocampus are related to memory problems and flashbacks.

If high amounts of stress hormones such as adrenalin are produced, the hippocampus can stop working properly, which causes flashbacks and nightmares to be continually repeated. This occurs because the malfunctioning hippocampus prevents flashbacks and nightmares from being processed properly.

However, if the stress is relieved and the levels of adrenalin return to normal, the brain begins to repair itself. Over time, the flashbacks and nightmares gradually disappear.

Diagnosing post-traumatic stress disorder (PTSD) can be difficult for two main reasons:

  • People who experience traumatic events often do not want to talk about their feelings.
  • people with PTSD may not seek treatment for many months or years after their symptoms appear.

When to seek medical advice

If you have experienced a traumatic event, such as a serious road traffic accident, you may develop PTSD.

Several criteria are used to help determine whether someone who has experienced or witnessed a traumatic event has PTSD. These include:

  • having vivid memories, flashbacks or nightmares,
  • trying to avoid things that remind you of the event,
  • sometimes feeling emotionally numb,
  • often feeling irritable and anxious for no apparent reason,
  • eating more than usual, drinking alcohol or using drugs more than usual,
  • being unable to control your mood,
  • finding it increasingly difficult to get on with others,
  • having to keep very busy to cope, and/or
  • feeling depressed or exhausted.

If it is less than six weeks since you experienced the traumatic event, and your symptoms are starting to improve, they may be part of the natural coping process.

However, discuss your feelings with your GP if your symptoms do not appear to be improving more than six weeks since the traumatic event.

Visiting your GP

As PTSD affects everyone differently, your GP will want to discuss your symptoms with you in as much detail as possible.

Your GP will ask you whether you have experienced a traumatic event, either in the recent or distant past, and whether you have re-experienced the event through flashbacks or nightmares. They may also ask you questions about your overall state of health, and whether you are having problems sleeping or you are having sleep disturbances.

If you have experienced a traumatic event, you may develop post-traumatic stress disorder (PTSD) in the days, weeks or months after the incident.

Although such events can be very difficult to come to terms with, confronting your feelings and seeking professional help is often the only way of effectively treating PTSD.


PTSD can be treated for many years after the traumatic event occurred, so it is never too late to seek help.

Treatment plan

Treatment for PTSD usually begins with a detailed evaluation and a treatment plan tailored to your individual needs. Your GP may feel that you would benefit from seeing a mental health specialist, such as:

  • a counsellor, who is trained to listen sympathetically and can help you to deal with any negative thoughts and feelings,
  • a psychologist, who is an expert in the workings of the mind,
  • a community psychiatric nurse, who specialises in mental healthcare, or
  • a psychiatrist: a mental health specialist who diagnoses and treats mental health conditions.

The healthcare professionals you are referred to should always treat you with sensitivity and understanding. Your treatment plan should be discussed with you. Any decisions regarding your treatment will be clearly explained.

Watchful waiting

'Watchful waiting' involves carefully monitoring your symptoms to see whether they improve or get worse. It may be recommended in cases of PTSD where symptoms are:

  • mild, and
  • have been present for less than four weeks after the traumatic event.

If watchful waiting is recommended, you should have a follow-up appointment within one month.


Psychotherapy is a type of talking therapy that is often effective in treating emotional problems and mental health conditions, including:

  • depression,
  • anxiety,
  • obsessive compulsive disorder (OCD), and
  • post-traumatic stress disorder (PTSD).

A psychotherapist is a trained mental health professional who will listen to your problems and suggest strategies that may help you to resolve them. In cases of severe or persistent PTSD, a combination of psychotherapy and medication may be recommended.

Cognitive behavioural therapy (CBT)

Cognitive behavioural therapy (CBT)is a type of psychotherapy that teaches you skills that will help you to change any negative thought processes you may have.

Trauma-focused CBT uses mental imagery of the traumatic event to help you work through the trauma and gain control of your fear and distress.

You may be offered trauma-focused CBT if:

  • you have severe symptoms of PTSD, which develop within one month of a traumatic event, or
  • you still have PTSD symptoms within three months of a traumatic event.

Between 8-12 weekly sessions of trauma-focused CBT are usually recommended, although fewer (about five) may be needed if the treatment starts within a month of the traumatic event.

Eye movement desensitisation and reprocessing (EMDR)

Eye movement desensitisation and reprocessing (EMDR) involves making several sets of side-to-side eye movements while recalling the traumatic incident.

EMDR aims to help your brain process flashbacks so that you can come to terms with the traumatic experience and think more positively. EMDR has been found to help many people with PTSD reduce their distress.


NICE suggests that paroxetine, which belongs to a group of medicines known as selective serotonin reuptake inhibitors (SSRIs), or the antidepressant mirtazapine, should be considered for treating PTSD in adults.

However, these medications should only be used when:

  • the person chooses not to have trauma-focused psychological treatment,
  • the person cannot start psychological treatment due to a high risk of further trauma,
  • the person has gained little or no benefit from a course of trauma-focused psychological treatment, or
  • there is severe depression or hypersensitivity, which significantly affects the person's ability to benefit from psychological treatment alone.

Amitriptyline or phenelzine may also be used under the supervision of a mental health specialist. The above criteria also apply.

SSRIs and antidepressants are also prescribed to reduce associated symptoms of depression and anxiety, and help with sleeping problems. SSRIs are not usually prescribed to people who are under 18 years old, unless they are recommended by a specialist.

If medication is prescribed for PTSD and it proves to be effective, it is usually continued for a minimum period of 12 months before being gradually withdrawn (over the course of four weeks or longer).

If a medication is ineffective, your dosage may be increased.

Before you are prescribed medication for PTSD, you doctor should inform you about any potential side effects and symptoms when the medication is withdrawn.

Side effects of paroxetine

Common side effects of paroxetine include:

  • nerve problems that may cause symptoms such as orofacial dystonias (muscle spasms around the face and mouth),
  • withdrawal syndrome (dependence on the medication),
  • yawning, and
  • raised cholesterol.

Less common side effects of paroxetine include:

  • arrhythmias (irregular heart beats),
  • temporary changes in blood pressure,
  • confusion, and
  • urinary incontinence (the unintentional passing of urine).

Rarer side effects of paroxetine may include:

  • panic attacks, and
  • depersonalisation (you experience an unreal or altered state, or you feel that your mind is separate from your body.

In very rare cases, paroxetine may cause:

  • peripheral oedema (fluid around your legs and ankles),
  • acute glaucoma (a severe but short-lived eye condition that affects vision),
  • hepatic disorders, such as hepatitis (liver inflammation), or
  • priapism (in men): a long-lasting, often painful, erection of the penis.

Children and young people

NICE recommends that trauma-focused CBT is used to treat older children with severe symptoms of PTSD in the first month after a traumatic event.

Three months after the trauma, the treatment advice outlined below is recommended.

  • A course of trauma-focused CBT, which is adapted to suit the child's age, circumstances and level of development.
  • A course of 8 to 12 trauma-focused sessions for children and young people who have chronic (long-term) PTSD following a traumatic event.
  • The psychological treatment should be regular and continuous (at least one session a week), and it should be delivered by the same person.
  • Where appropriate, the child and their family should be involved in the treatment plan.
  • Where appropriate, the child's parents or guardians should be informed that trauma-focused psychological treatments have proved to be an effective method of treating PTSD. They should also be told that there is no evidence that other forms of therapy, such as play therapy, art therapy or family therapy, are effective.

Disaster planning

Following disasters, healthcare and social services are responsible for arranging the appropriate social care and psychological support for everyone affected, including survivors and their relatives.

NICE recommends that there should be a planned psychological response to a disaster, which should contain:

  • provision for immediate practical help,
  • means to support the affected communities in caring for those involved in the disaster, and
  • the provision of specialist mental health, evidence-based assessment and treatment services.

The plan should ensure that all healthcare workers have clear roles and responsibilities that are agreed in advance.

Content provided by NHS Choices and adapted for Ireland by the Health A-Z.

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