This page is for general education and is not medical advice. It is not a substitute for diagnosis or treatment by a qualified professional. If this is an emergency, call 911 or 988.
There is no single lab test for PTSD — diagnosis is clinical. A qualified professional talks with you about your symptoms, your history, and how daily life is affected, and may use standardized screening tools. For a PTSD diagnosis, symptoms generally last more than a month and cause real distress or problems functioning. Knowing what an evaluation involves can make reaching out feel less daunting.
Key facts
- PTSD is diagnosed through clinical evaluation, not a blood test or scan (NIMH).
- A diagnosis generally requires symptoms lasting more than a month, with significant distress or impairment (MedlinePlus).
- Intense symptoms within the first month after trauma may instead meet criteria for acute stress disorder (VA, National Center for PTSD).
- Professionals also screen for other conditions, such as depression or substance use, that often occur alongside PTSD (NIMH).
What an evaluation involves
- A conversation about the traumatic event (or events), your symptoms, and how long they have lasted
- Questions about the impact on work, relationships, sleep, and daily life
- Standardized screening questionnaires, in some cases
- A review of physical health and other conditions that can cause or worsen symptoms
The one-month criterion
Short-term stress reactions after trauma are common and often ease on their own. A PTSD diagnosis applies when core symptoms persist beyond about a month and interfere with daily life. If symptoms are intense but very recent, a clinician may consider acute stress disorder instead.
How to prepare
It can help to jot down your main symptoms, when they started, and how they affect your day. A private PTSD self-check can help you organize your thoughts — but it is a starting point, not a diagnosis.
Why a professional matters
Only a qualified professional can diagnose PTSD, distinguish it from conditions with overlapping symptoms, and recommend treatment that fits your situation.
From our clinical review. People expect the evaluation to be an interrogation about the worst day of their life. It is not. A good clinician follows your lead, asks only what is needed, and spends as much time on how you are functioning now as on what happened then.
When you are ready, see PTSD treatment options — or take a private, two-minute PTSD self-check to help you prepare.
Frequently asked questions
How is PTSD diagnosed?
There is no blood test or scan for PTSD. A qualified professional makes the diagnosis through a clinical interview about your symptoms, history, and how daily life is affected, sometimes using standardized questionnaires. They also rule out other conditions that can cause similar symptoms.
How long must symptoms last to be diagnosed as PTSD?
For a PTSD diagnosis, symptoms generally last more than a month and cause significant distress or problems functioning. When intense symptoms appear within the first month after trauma, clinicians may diagnose acute stress disorder instead. Only a professional can make either diagnosis.
Can I diagnose myself with an online quiz?
No. Online self-checks can help you notice patterns and decide whether to reach out, but they cannot diagnose PTSD. A diagnosis requires evaluation by a qualified professional, who can also identify other conditions and recommend treatment.
Sources
- Post-Traumatic Stress Disorder (PTSD) — National Institute of Mental Health (NIMH)
- Post-Traumatic Stress Disorder — MedlinePlus, U.S. National Library of Medicine
- PTSD: National Center for PTSD — U.S. Department of Veterans Affairs (VA)
Reviewed against the sources above. This page is educational and is not medical advice.