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Posttraumatic stress disorder (PTSD): Symptoms, causes, and treatments

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What Is Posttraumatic Stress Disorder (PTSD)?

Posttraumatic stress disorder is a mental health disorder that occurs after a person witnesses or experiences trauma. Trauma is an emotional response to a terrifying or threatening event, relationship, or circumstance that jeopardizes or harms a person’s physical, mental, or emotional health and safety.

A Brief History of PTSD and Diagnosing Trauma

Although trauma has existed throughout human history, it wasn’t until 1980 that the American Psychological Association (APA) added the term “PTSD” to its authoritative diagnostic manual, the DSM, in its third edition.

This change came in part due to the prevalence of veterans returning from the Vietnam War with a history of trauma. However, this new diagnosis covered trauma of all kinds, not just trauma experienced on the battlefield.

PTSD Symptoms

Recent research shows that about 7–8% of people in the United States will have PTSD at some point in their lives. However, not everyone who experiences or witnesses trauma will develop PTSD. In fact, individuals who have been directly or indirectly exposed to trauma must exhibit  the following four symptoms to meet criteria for PTSD:

  1. Intrusive memories: Also known as reliving or reexperiencing, people with PTSD will unwillingly remember or relive their trauma. This can occur in the form of distressing memories, flashbacks, or nightmares.
  2. Avoidance: People with PTSD will purposefully try to avoid situations, people, places, thoughts, or memories associated with their trauma, also known as triggers.
  3. Cognition/mood changes: PTSD changes the way you think and feel. You may struggle to remember certain things, even information that is unrelated to your trauma. Emotionally, you may experience feelings of hopelessness, numbness, or detachment.
  4. Arousal/reactivity: People with PTSD often feel constantly on guard. This state of heightened arousal is known as hypervigilance, and it is characterized by insomnia, irritability, anxiety, rapid heartbeat, muscle tension, and more. It can also result in greater reactivity to stress, characterized by irritability, intense guilt and shame, and angry outbursts.

To be diagnosed with PTSD, a person has to experience all four symptoms for at least a month in a way that interferes with their ability to function.

Reactions to Trauma

Not everyone who experiences trauma will react the same way. Following a traumatic event, the following reactions may occur:

    • Normal stress response: When someone is exposed to an isolated stressor or traumatic event, they may experience a variety of symptoms that are associated with the body’s “fight-or-flight” response, including anxiety, increased heart rate, and muscle tension. These effects typically fade shortly after the stressor resolves.
    • Acute stress disorder: The criteria for acute stress disorder (ASD) are similar to those for PTSD, with the difference being that ASD symptoms persist for less than a month. If the symptoms continue beyond this time frame, then the person’s diagnosis is changed to posttraumatic stress disorder.
    • Uncomplicated PTSD: People with uncomplicated PTSD do not struggle with any co-occurring mental health disorders. As a result, the only focus of treatment involves addressing the person’s trauma-related symptoms.
    • Comorbid PTSD: Some people with PTSD already struggle with a preexisting mental health disorder, such as anxiety or depression. Others develop a co-occurring mental health condition after they experience trauma. The mental health disorders that most frequently occur alongside PTSD include major depression, anxiety, and substance use disorders.
    • Complex PTSD: Some traumas are single events that impact our lives dramatically, such as a car accident or a natural disaster. Other traumas take place over time, such as an abusive relationship or a year-long deployment to a warzone. Someone who suffers from long-term trauma or multiple traumas may be diagnosed with complex PTSD.

What Causes PTSD?

Trauma is the cause of PTSD. PTSD literally stands for posttraumatic stress disorder, which means that it develops after someone experiences or witnesses trauma. This criterion sets PTSD apart from other mental health conditions that do not require an identifiable cause (such as exposure to trauma) for a diagnosis.

What Is Trauma?

Trauma reflects how we respond to terrifying or disturbing events and circumstances that threaten or harm our physical, mental, or emotional health and safety. Traumatic events are surprisingly common: about 60% of men and 50% of women will experience trauma at some point in their lives.

Big “T” Trauma and Little “t” Trauma

Many people wonder, “What counts as trauma?” Our culture tends to reserve the word “trauma” for extreme danger or acts of violence. However, trauma is all about our response, not the specific events or circumstances themselves.

This means that more ordinary situations can still “count” as trauma. One helpful way to think about this wider definition of trauma is big “T” trauma and little “t” trauma.

Big “T” trauma covers the extreme, terrifying, life-altering events and circumstances our culture already tends to associate with the word “trauma,” such as:

    • Sexual violence
    • Physical abuse
    • War
    • Natural disasters
    • Severe car accidents

Little “t” trauma refers to distressing circumstances that are not life-threatening but can still produce a trauma response, such as:

    • Divorce
    • Bullying
    • Getting fired
    • Unresolved relational conflicts
    • Financial or legal difficulties

Multiple little “t” traumas can end up having as detrimental an effect on our mental health as one big “T” trauma. You don’t have to know the source of your trauma to seek help. Just because you haven’t gone through a big “T” trauma doesn’t mean you can’t have PTSD.

Experiencing vs. Witnessing Trauma

It makes sense that if you directly experience trauma, you may develop PTSD. But did you know that even just witnessing trauma can cause PTSD?

Trauma is our response to danger and threats, real or perceived. Even if you were completely safe from the trauma you witnessed, your body may still have reacted to a perceived threat.

This is common among first responders, who are tasked with responding to catastrophic events where individuals have been severely injured or even killed. Even though there is no threat to their physical well-being, just witnessing someone else’s lost life can trigger a trauma response.

Witnessing trauma is especially prevalent among children. A child may not be subject to physical abuse, but they can still develop PTSD if they witness one parent being violent toward the other. Even witnessing national disasters on television, such as 9/11 or a school shooting, can trigger a trauma response.

PTSD Treatment

The good news is that PTSD is treatable. Many people with PTSD improve greatly with treatment. There are many options for treatment when it comes to PTSD, including:

    • Cognitive behavioral therapy (CBT) : CBT can help you identify and replace unhelpful thought patterns that fuel your emotions and behaviors. For example, people with PTSD often overgeneralize the likelihood of bad events happening, and CBT can help counter and address these patterns of thinking.
    • Prolonged exposure therapy: Exposure therapy allows survivors of trauma to relive their trauma in a safe, controlled environment. By confronting their memories and emotions head-on, people with PTSD can gradually dissociate fear and anxiety from their traumatic experience and learn how to move forward.
    • Eye movement desensitization and reprocessing (EMDR): EMDR therapy allows people with PTSD to process traumatic memories they may have been blocking. It engages a person’s eyes in a similar way to REM sleep, allowing a person to access traumatic memories in a way that encourages new connections and rapid processing.
    • Medication: Certain antidepressants may help ease some of the symptoms of PTSD. Typically, medication is prescribed alongside other forms of treatment.
    • Group therapy: Many people with PTSD find support through group therapy with individuals who have survived the same trauma.
    • Animal assistance: A service animal, therapy animal, or emotional-support animal may help ease symptoms of PTSD.

Find a Therapist Who Treats PTSD Near You

Therapy is a great treatment option for PTSD. To find a trauma-informed therapist near you, click here. You can also search specifically for a counselor who specializes in EMDR therapy by clicking here.

Get Help Now

If you are suffering from PTSD and currently in crisis, help is available now:

Frequently Asked Questions (FAQs)

I’m Not a Veteran. Can I Still Have PTSD?

Yes. Anyone can be diagnosed with PTSD, even if they have never served in the military. People develop PTSD after experiencing a trauma, including but not limited to warfare.

Is Acute Stress Disorder (ASD) a Type of PTSD?

No. ASD is a short-term response to trauma that lasts less than a month. Although some people with ASD can develop PTSD, many cases of ASD resolve on their own.

Is PTSD a Mental Illness?

Yes, PTSD is a mental health disorder. Specifically, the DSM-5 classifies PTSD as a trauma and stressor-related disorder. This means that people with PTSD will likely not improve unless they seek professional treatment. The good news is that PTSD is treatable.

What Are PTSD Triggers?

People with PTSD have triggers that cause them to experience overwhelming physical or emotional responses, such as rapid heartbeat, difficulty breathing, and flashbacks of the trauma itself. These triggers often include certain sights, smells, or sounds that remind the person of the traumatic event. A person’s triggers will depend on the trauma they experienced. For example, if you were seriously injured in a car accident, driving may trigger some PTSD symptoms.

PTSD triggers do not have to last forever. Many people with PTSD learn how to overcome their triggers with professional treatment.

What If I Don’t Remember My Trauma?

Trauma affects our cognition, which means that you may struggle with memory problems after going through a traumatic event. You may even block your memory of the trauma itself.

It’s okay if your memories of a traumatic event are fuzzy or unclear, or even if you don’t remember the trauma at all. A therapist can help you unlock those memories safely so you can process them and integrate them into your sense of self. EMDR therapy in particular is helpful in recovering memories after trauma.

How Do You Know If You Have PTSD?

The only way to be certain that you have PTSD is to receive a diagnosis from a mental health professional. So when should you seek professional help?

You can start going to therapy whenever you want for whatever reason. However, if you’re wondering if you have PTSD, it’s a good idea to seek treatment if you’re struggling with symptoms in the weeks or months after a traumatic event.

Keep in mind that multiple little “t” traumas over the course of a lifetime may result in PTSD, even if you don’t think you have experienced trauma. Also, some people block memories of their trauma, so you may not remember having gone through a trauma in the first place.

A good rule of thumb is to seek professional help simply if you want it. Instead of trying to determine if you meet a certain threshold of trauma or stress on your own, find a therapist who has the skills and experience to help you process your memories and emotions—no matter what diagnosis you may or may not receive.

About the author

The editorial team at works with the world’s leading clinical experts to bring you accessible, insightful information about mental health topics and trends.

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