Post-traumatic stress disorder (PTSD) has a specific meaning. It is not a word for every hard reaction to a frightening event.
This article describes the symptom groups clinicians look for, how long symptoms must last, how PTSD can appear late, and how common it is. It is a description and not a test. Reading a list cannot tell you whether you have PTSD, and nothing here asks you to go back over what happened. The VA's National Center for PTSD is direct about it: "Only a mental health provider can diagnose PTSD."
What are the four groups of PTSD symptoms?
The VA says: "There are 4 types of PTSD symptoms. To be diagnosed with PTSD, you need to have each type." The names below are the VA's. The examples come from the VA and the National Institute of Mental Health (NIMH).
- Reliving the event (also called re-experiencing). Recurring memories or dreams related to the event, distressing thoughts, physical signs of stress, and flashbacks, which the VA describes as feeling like you are going through the event again. See flashbacks, nightmares and triggers.
- Avoiding things that remind you of the event. Staying away from places, events or objects that are reminders, and avoiding thoughts or feelings related to the event.
- Having more negative thoughts and feelings than before the event. NIMH lists ongoing negative emotions such as fear, anger, guilt or shame, negative thoughts about oneself or the world, loss of interest in previous activities, feelings of social isolation, and trouble remembering key features of the event. The VA adds feeling numb.
- Feeling on edge or keyed up (also called hyperarousal). Being easily startled, feeling tense or on guard, difficulty concentrating, difficulty falling or staying asleep, and feeling irritable or having angry outbursts.
The VA adds that "everyone experiences symptoms in their own way."
How long do symptoms have to last?
Longer than one month. NIMH says: "To meet the criteria for PTSD, a person must have symptoms for longer than 1 month, and the symptoms must be severe enough to interfere with aspects of daily life, such as relationships or work." The symptoms also must be unrelated to medication, substance use or other illness.
In the first month, strong reactions are common and are not PTSD. After a traumatic event covers that period, including acute stress disorder.
Can PTSD start months or years after the event?
Yes. NIMH says symptoms "usually begin within 3 months of the traumatic event, but they sometimes emerge later." The VA says they "may not appear until months or years later."
Clinicians have a term for this. The 2023 VA/DoD guideline says PTSD can have a delayed expression, "where full diagnostic criteria are unmet until at least six months after exposure to the traumatic event." The VA's page on the diagnostic manual adds that the onset of symptoms may still occur immediately. So delayed means the full picture arrives late. It does not mean there were no symptoms before.
How common is PTSD?
Less common than exposure to trauma. The VA says: "Most people who go through a traumatic event will not develop PTSD." Its best estimates are:
- About 6 of every 100 people in the U.S. will have PTSD at some point in their lives.
- About 5 of every 100 adults in the U.S. have PTSD in any given year.
- About 8 of every 100 women and 4 of every 100 men will have PTSD at some point in their life.
A VA page written for providers reports the same figures from a national survey of more than 36,000 U.S. adults carried out in 2012 and 2013 using DSM-5 criteria. You may also see older NIMH figures: 3.6% of adults in the past year and 6.8% over a lifetime. Those are from a survey conducted between 2001 and 2003 under the earlier DSM-IV definitions. The VA itself says the exact number of people who have PTSD is not known.
How do clinicians assess PTSD?
By asking questions. The VA says an assessment "includes answering questions about your thoughts, feelings and behaviors." Some evaluations take as little as 15 minutes, and a more thorough one takes about 1 to 2 hours. The VA says a good assessment can be done without any special equipment.
You stay in charge of what you share. The VA says: "You will be in control of how much information you share about any traumas you experienced. You can always ask to take a break if helpful."
NIMH says a mental health professional, such as a psychiatrist, psychologist or clinical social worker, can determine whether symptoms meet the criteria for PTSD. Short questionnaires called screens also exist. A screen can show that further assessment is worthwhile. It is not a diagnosis. Do I need trauma therapy? explains what screens are for.
What else can come with PTSD?
Other conditions often do. NIMH says: "People with PTSD often have co-occurring conditions, such as depression, substance use, or one or more anxiety disorders." The VA's National Center for PTSD, introducing its pages for providers on co-occurring conditions, says most people with PTSD, about 80%, have one or more additional mental health diagnoses. The page does not name the study behind that figure.
PTSD itself is no longer classed as an anxiety disorder. In 2013, DSM-5 moved it into a new category, Trauma- and Stressor-Related Disorders. Anxiety and trauma explains how the two relate.
Related topics have articles of their own: complex PTSD, dissociation and emotional numbness, and trauma, alcohol and substance use.
What should you do if this sounds familiar?
Ask for an assessment. The VA says to talk to a doctor or mental health care provider if your symptoms last longer than a month, are very upsetting, or disrupt your daily life. If you are thinking about harming yourself, call or text 988, or call 911 in an emergency.
Treatments for PTSD have been studied, and U.S. guidelines most strongly recommend specific trauma-focused psychotherapies. The 2023 VA/DoD guideline names cognitive processing therapy, EMDR and prolonged exposure. The American Psychological Association's 2025 guideline names cognitive processing therapy, prolonged exposure and trauma-focused cognitive behavioral therapy. Both found insufficient evidence to recommend for or against psychodynamic therapy, which has been studied much less for PTSD. Types of trauma therapy sets out the research.
Dr. Rabin's trauma therapy page speaks of PTSD, intrusive memories, flashbacks and nightmares, avoidance, hypervigilance, and numbness and disconnection. Her approach is psychodynamic, attachment-based, trauma-informed and mindfulness-based, guided by safety, pacing and the therapeutic relationship. The client decides what is discussed and when. You can request a free consultation of about 15 minutes through the contact page and ask whether she offers a particular treatment or would refer you.
Keep reading
Sources
- National Institute of Mental Health, Post-Traumatic Stress Disorder, NIH Publication No. 23-MH-8124 (revised 2023)
- VA National Center for PTSD, PTSD Basics (page header: Last Updated October 2026)
- U.S. Department of Veterans Affairs and Department of Defense, VA/DoD Clinical Practice Guideline for Management of Posttraumatic Stress Disorder and Acute Stress Disorder (June 2023)
- VA National Center for PTSD, PTSD and DSM-5 (last updated September 28, 2026)
- VA National Center for PTSD, How Is PTSD Assessed? (last updated September 25, 2026)
- VA National Center for PTSD, How Common is PTSD in Adults? (last updated September 25, 2026)
- VA National Center for PTSD, Epidemiology and Impact of PTSD (last updated August 20, 2026)
- National Institute of Mental Health, Statistics: Post-Traumatic Stress Disorder (NCS-R 2001 to 2003)
- VA National Center for PTSD, Co-Occurring Conditions (last updated September 28, 2026)
- American Psychological Association, Clinical Practice Guideline for the Treatment of Posttraumatic Stress Disorder (PTSD) in Adults (2025)
Last reviewed October 2026. This guide is general information, not medical advice or a diagnosis. If you are in crisis or thinking about harming yourself, call or text 988, or call 911 in an emergency.
