Post-Traumatic Stress Disorder


Post-traumatic stress disorder (PTSD) is a complex psychiatric condition that specifically involves anxiety. It may also be written as posttraumatic stress disorder. People develop PTSD after they experience or witness an event that is perceived to be a threat or considered to be life-threatening and in which they experience fear, terror, or helplessness.


PTSD is sometimes summarized as “a normal reaction to abnormal events.” It was first defined as a distinctive disorder in 1980. Originally diagnosed in veterans of the Vietnam War (1955–1975), it is now recognized in civilian survivors of rape or other criminal assaults; natural disasters; aircraft crashes, train collisions, serious accidents, or industrial explosions; acts of terrorism; child abuse; or military combat. Most people who have experienced such trauma return to a normal life. However, some people continue to experience the stress of reliving such trauma, often in the form of nightmares, flashbacks, sleep problems, and other such symptoms that impair daily life. These persons may develop PTSD.

Soldiers in the early nineteenth century were diagnosed by medical doctors with exhaustion after experiencing the trauma and stress of war. Often these soldiers displayed degraded mental facilities that sometimes included physical symptoms, which forced them into treatment until their symptoms subsided and they could return to combat. Although these soldiers were diagnosed with such terms as battle fatigue, shell shock, and stress syndrome, the medical community did not recognize PTSD until the 1970s, during the Vietnam War.

The experience of PTSD has sometimes been described as being in a horror film that keeps replaying and cannot be shut off. It is common for people with PTSD to feel intense fear and helplessness, and to relive the frightening event in nightmares or in their waking hours. Sometimes the memory is triggered by a sound, smell, or image that reminds the individual of the traumatic event. These re-experiences of the event are called flashbacks. Persons with PTSD are likely to be jumpy and easily startled or to go numb emotionally and lose interest in activities they used to enjoy. They may have problems with memory and with getting enough sleep. In some cases, they may feel disconnected from the real world or have moments in which their own bodies seem unreal. These symptoms are indications of dissociation, a process in which the mind splits off certain memories or thoughts from conscious awareness. Many people with PTSD turn to alcohol or drugs in order to escape the flashbacks and other symptoms of the disorder, even if only for a few minutes.

Risk factors

Factors that influence the likelihood of a person developing PTSD include:

HIGH-RISK POPULATIONS. About 8% of Americans experience PTSD at some point in their lives; however, women (10.4%) are just over twice as likely as men (5%) to develop PTSD. Around 3.5% of adults in the United States from the age of 18 to 54 years have PTSD during any given year. Some subpopulations in the United States are at greater risk of developing PTSD. The lifetime prevalence of PTSD among persons living in depressed urban areas or on Native American reservations is estimated at 23%. For victims of violent crimes, the estimated rate is 58%.

PTSD also appears to be more common in seniors than in younger people. Thirteen percent of the members of a senior population report they are affected by PTSD in comparison to 7–10% of the entire population. Reports of elder abuse crimes have increased 200% since 1986. In addition, the incidence of PTSD is known to be higher in Holocaust survivors, war veterans, and cancer or heart surgery survivors, which account for a significant portion of older Americans. Of those seniors who are military veterans, there is an increasing number who are isolated and/or in poor health as a result of PTSD.

Children are also susceptible to PTSD and their risk is increased exponentially as their exposure to the event increases. Children experiencing abuse, the death of a parent, or those located in a community experiencing a traumatic event can develop PTSD. Two years after the Oklahoma City (Oklahoma) bombing of 1995, 16% of children within a 100-mi. (160-km) radius of Oklahoma City with no direct exposure to the bombing had increased symptoms of PTSD. Weak parental response to the event, having a parent with PTSD symptoms, and intensified exposure to the event via the media all increase the possibility of a child developing PTSD symptoms. In addition, a developmentally inappropriate sexual experience for a child may be considered a traumatic event, even though it may not have actually involved violence or physical injury.

MILITARY VETERANS. Studies conducted between 2004 and 2006 with veteran participants from Operation Iraqi Freedom and Operation Enduring Freedom (Afghanistan) found a strong correlation between duration of combat exposure and PTSD. Veterans of combat in Iraq reported a higher rate of PTSD than those deployed to Afghanistan because of longer exposure to warfare.

Information about PTSD in veterans of the Vietnam era is derived from the National Vietnam Veterans Readjustment Survey (NVVRS), conducted between 1986 and 1988. The estimated lifetime prevalence of PTSD among American veterans of this war is 31% for men and 27% for women. An additional 22.5% of the men and 21% of the women have been diagnosed with partial PTSD at some point in their lives. The lifetime prevalence of PTSD among veterans of World War II (1939–1945) and the Korean War (1950–1953) is estimated at 20%.

Generally, military personnel, whether men or women, who have spent time in war zones experience PTSD about 30% of the time. Another 20–25% of these veterans are diagnosed with partial PTSD at some time after their military experiences. In the 2010s, estimates of PTSD in U.S. military personnel who served in Iraq vary from 12% to 20%.

CROSS-CULTURAL ISSUES. Further research needs to be done on the effects of ethnicity and culture on post-traumatic symptoms. As of the early 2010s, Western clinicians working with patients from a similar background have done most PTSD research. Researchers do not yet know whether persons from non-Western societies have the same psychological reactions to specific traumas or whether they develop the same symptom patterns.


PTSD can develop in almost anyone in any age group exposed to a sufficiently terrifying event or chain of events. The National Institute of Mental Health (NIMH) states, “Anyone can get PTSD at any age. This includes war veterans and survivors of physical and sexual assault, abuse, accidents, disasters, and many other serious events. Not everyone with PTSD has been through a dangerous event. Some people get PTSD after a friend or family member experiences danger or is harmed. The sudden, unexpected death of a loved one can also cause PTSD.”

The NIMH estimated in 2007, the last year in which it was reported, that about 7.7 million adults in the United States have PTSD. One study found that 3.7% of a sample of teenage boys and 6.3% of adolescent girls had PTSD. It is estimated that a person's risk of developing PTSD over the course of their life is between 8% and 10%. On average, 30% of soldiers who have been in a war zone develop PTSD. Women are at greater risk of PTSD following sexual assault or domestic violence, while men are at greater risk of developing PTSD following military combat.

Traumatic experiences are surprisingly common in the general North American population. More than 10% of the men and 6% of the women in one survey reported experiencing four or more types of trauma in their lives. The most frequently mentioned traumas are:

PTSD is more likely to develop in response to an intentional human act of violence or cruelty such as a rape or mugging than as a reaction to an impersonal catastrophe like a flood or hurricane. It is not surprising that the traumatic events most frequently mentioned by men diagnosed with PTSD are rape, combat exposure, childhood neglect, and childhood physical abuse. For women diagnosed with PTSD, the most common traumas are rape, sexual molestation, physical attack, being threatened with a weapon, and childhood physical abuse.

PTSD can also develop in therapists, rescue workers, or witnesses of a frightening event as well as in those who were directly involved. This process is called vicarious traumatization.

Causes and symptoms

The causes of PTSD are not completely understood. One major question that has not been answered, is why some people involved in a major disaster develop PTSD and other survivors of the same event do not. For example, a survey of 988 adults living close to the World Trade Center conducted in November 2001 found that only 7% had been diagnosed with PTSD following the events of September 11th; the other 93% were anxious and upset, but they did not develop PTSD. Research into this question is ongoing in the 2010s.


BIOCHEMICAL/PHYSIOLOGICAL CAUSES. Present neurobiological research indicates that traumatic events cause lasting changes in the human nervous system, including abnormal levels of secretion of stress hormones. In addition, in PTSD patients, researchers have found changes in the amygdala and the hippocampus—the parts of the brain that form links between fear and memory. Experiments with ketamine, a drug that inactivates one of the neurotransmitters in the central nervous system, suggest that trauma works in a similar way to damage associative pathways in the brain. Positron emission tomography (PET) scans of PTSD patients suggest that trauma affects the parts of the brain that govern speech and language.

SOCIOCULTURAL CAUSES. Studies of specific populations of PTSD patients (such as combat veterans, survivors of rape or genocide, and former political hostages or prisoners) have shed light on the social and cultural causes of PTSD. In general, societies that are highly authoritarian, glorify violence, or sexualize violence have high rates of PTSD even among civilians.

OCCUPATIONAL FACTORS. Persons whose work exposes them to traumatic events or who treat trauma survivors may develop secondary PTSD (also known as compassion fatigue or burnout). These occupations include specialists in emergency medicine, police officers, firefighters, search-and-rescue personnel, psychotherapists, and disaster investigators. The degree of risk for PTSD is related to three factors: (1) the amount and intensity of exposure to the suffering of trauma victims, (2) the worker's degree of empathy and sensitivity, and (3) unresolved issues from the worker's personal history.

PERSONAL VARIABLES. Although the most important causal factor in PTSD is the traumatic event itself, individuals differ in the intensity of their cognitive and emotional responses to trauma; some persons appear to be more vulnerable than others. In some cases, this greater vulnerability is related to temperament or natural disposition, with shy or introverted people being at greater risk. In other cases, the person's vulnerability results from chronic illness, a physical disability, or previous traumatization—particularly abuse in childhood. As of 2012, researchers have not found any correlation between race or ethnicity and biological vulnerability to PTSD. The NIMH states, “Researchers are studying the importance of various risk and resilience factors. With more study, it may be possible someday to predict who is likely to get PTSD and prevent it.”


DSM-5 specifies six diagnostic criteria for PTSD:


The diagnosis of PTSD is based on the patient's history, including the timing of the traumatic event and the duration of the patient's symptoms.


Consultation with a mental health professional for diagnosis and a plan of treatment is always advised. Many of the responses to trauma, such as shock, terror, irritability, blame, guilt, grief, sadness, emotional numbing, and feelings of helplessness, are natural reactions. For most people, resilience is an overriding factor and trauma effects diminish within 6 to 16 months. It is when these responses continue or become debilitating that PTSD is often diagnosed.

As outlined in DSM-IV, exposure to a traumatic stressor means that an individual experienced, witnessed or was confronted by an event or events involving death or threat of death, serious injury or the threat of bodily harm to oneself or others. The individual's response must involve intense fear, helplessness, or horror. A two-pronged approach to evaluation is considered the best way to make a valid diagnosis because it can gauge under-reporting or over-reporting of symptoms. The two primary forms are structured interviews and self-report questionnaires. Spouses, partners, and other family members may also be interviewed. Because the evaluation may involve subtle reminders of the trauma in order to gauge a patient's reactions, individuals should ask for a full description of the evaluation process beforehand. Asking what results can be expected from the evaluation is also advised.

A number of structured interview forms have been devised to facilitate the diagnosis of PTSD:

Self-reporting checklists provide scores to represent the level of stress experienced. Some of the most commonly used checklists are:


There are no laboratory or imaging tests that can detect PTSD, although the doctor may order imaging studies of the brain to rule out head injuries or other physical causes of the patient's symptoms.


Treatment for post-traumatic stress disorder includes both traditional and alternative methods.

Treatment for PTSD usually involves a combination of medications and psychotherapy. If patients have started to abuse alcohol or drugs, they must be treated for the substance abuse before being treated for PTSD. If the patient is diagnosed with coexisting depression, treatment should focus on the PTSD because its course, biology, and treatment response are different from those associated with major depression. Patients with the disorder are usually treated as outpatients; they are not hospitalized unless they are threatening to commit suicide or harm other people.

Mainstream forms of psychotherapy used to treat patients who have already developed PTSD include:


Medications are used most often in patients with severe PTSD to treat the intrusive symptoms of the disorder as well as feelings of anxiety and depression. These drugs are usually given as one part of a treatment plan that includes psychotherapy or group therapy. As of 2012, there is no single medication used to treat PTSD. The selective serotonin reuptake inhibitors (SSRIs), which are a class of compounds often used as antidepressants, appear to help the core symptoms when given in higher doses for five to eight weeks, while the tricyclic antidepressants (TCAs) or the monoamine oxidase inhibitors (MAOIs) are most useful in treating anxiety and depression.

Sleep problems can be lessened with brief treatment with an anti-anxiety drug, such as a benzodiazepine like alprazolam (Xanax), but long-term usage can lead to disturbing side effects, such as increased anger, drug tolerance, dependency, and abuse. Benzodiazepines are also not given to PTSD patients diagnosed with coexisting drug or alcohol abuse.

Alternative treatment

Relaxation training, which is sometimes called anxiety management training, includes breathing exercises and similar techniques intended to help the patient prevent hyperventilation and relieve the muscle tension associated with the fight-or-flight reaction of anxiety. Yoga, aikido, t'ai chi, and dance therapy help patients work with the physical as well as the emotional tensions that either promote anxiety or are created by the anxiety.

Other alternative or complementary therapies are based on physiological and/or energetic understanding of how the trauma is imprinted in the body. These therapies affect a release of stored emotions and resolution of them by working with the body rather than merely talking through the experience. One example of such a therapy is Somatic Experiencing (SE), developed by American therapist Peter Levine (1942–). SE is a short-term, biological, body-oriented approach to PTSD or other trauma. This approach heals by emphasizing physiological and emotional responses, without re-traumatizing the person, without placing the person on medication, and without the long hours of conventional therapy.

When used in conjunction with therapies that address the underlying cause of PTSD, such relaxation therapies as hydrotherapy, massage therapy, and aromatherapy are useful to some patients in easing PTSD symptoms. Essential oils of lavender, chamomile, neroli, sweet marjoram, and ylang-ylang are commonly recommended by aromatherapists for stress relief and anxiety reduction.

Some patients benefit from spiritual or religious counseling. Because traumatic experiences often affect patients' spiritual views and beliefs, counseling with a trusted religious or spiritual advisor may be part of a treatment plan. A growing number of pastoral counselors in the major Christian and Jewish bodies in North America have advanced credentials in trauma therapy. Native Americans are often helped to recover from PTSD by participating in traditional tribal rituals for cleansing memories of war and other traumatic events. These rituals may include sweat lodges, prayers and chants, or consultation with a shaman or tribal healer.

Several controversial methods of treatment for PTSD have been introduced since the mid-1980s. Mainstream medical researchers have developed some methods, while others are derived from various forms of alternative medicine. These methods are controversial because they do not offer any scientifically validated explanations for their effectiveness. They include:

Public health role and response

The United States offers help with PTSD through its National Center for PTSD—headquartered in Washington, D.C.—which is a part of the Department of Veterans Affairs (VA). Its website ( ) states, “We are the center of excellence for research and education on the prevention, understanding, and treatment of PTSD. Our Center has seven divisions across the country. Although we provide no direct clinical care, our purpose is to improve the well-being and understanding of American Veterans. We conduct cutting edge research and apply resultant findings to: ‘Advance the Science and Promote Understanding of Traumatic Stress.’” These seven divisions are:

A class of drugs that have a hypnotic and sedative action, used mainly as tranquilizers to control symptoms of anxiety.
Cognitive-behavioral therapy—
A type of psychotherapy used to treat anxiety disorders (including PTSD) that emphasizes behavioral change as well as alteration of negative thought patterns.
A hormone produced by the adrenal glands near the kidneys in response to stress.
The splitting off of certain mental processes from conscious awareness. Many PTSD patients have dissociative symptoms.
A temporary reliving of a traumatic event.
A state of increased emotional tension and anxiety, often including jitteriness and being easily startled.
A condition of abnormally intense watchfulness or wariness. It is one of the most common symptoms of PTSD.
The percentage of a population that is affected by a specific disease at a given time.
Selective serotonin reuptake inhibitors (SSRIs)—
A class of antidepressants that work by blocking the reabsorption of serotonin in the brain, raising the levels of serotonin. Examples include Prozac, Zoloft, and Paxil.
A severe injury or shock to a person's body or mind.


The prognosis of PTSD is difficult to determine because patients' personalities and the experiences they undergo vary widely. A majority of patients get better, including some who do not receive treatment. One study reported that the average length of PTSD symptoms in patients who get treatment is 32 months, compared to 64 months in patients who are not treated.


About 30% of people with PTSD never recover completely. A few commit suicide because their symptoms get worse rather than improving.


PTSD is impossible to prevent completely because natural disasters and human acts of violence will continue to occur. In addition, it is not possible to tell beforehand how any given individual will react to a specific type of trauma. Prompt treatment after a traumatic event may lower the survivor's risk of developing severe symptoms.

See also Gulf war syndrome .



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American Psychiatric Association, 1000 Wilson Blvd, Ste. 1825, Arlington, VA, 22209-3901, (703) 907-7300, (888) 357-7924,, .

Anxiety Disorders Association of America, 8701 Georgia Ave., Ste. 412, Silver Spring, MD, 20910, (240) 485-1001, .

International Society for Traumatic Stress Studies, 111 Deer Lake Rd., Ste. 100, Deerfield, IL, 60015, (847) 480-9028, Fax: (847) 480-9282, .

National Alliance on Mental Illness, 3803 N. Fairfax Dr., Ste. 100, Arlington, VA, 22203, (703) 524-7600, Fax: (703) 524-9094, (800) 950-6264, .

National Center for Posttraumatic Stress Disorder, 810 Vermont Ave. NW, Washington, DC, 20420, .

National Institute of Mental Health, 6001 Executive Bvld, Rm. 8184, MSC 9663, Bethesda, MD, 20892-9663, (301) 443-4513, Fax: (301) 443-4279, (866) 615-6464,, .

Rebecca J. Frey, PhD
Revised by William A. Atkins, BB, BS, MBA

  This information is not a tool for self-diagnosis or a substitute for professional care.