A diagnosis is made via a medical professional’s evaluation, and sometimes tests to rule out other possible causes.
Medical professionals suspect the disorder based on symptoms:
- Individuals have episodes of depersonalisation, derealisation, or both that last a long time or recur.
- Individuals know that their unreal experiences are not real.
- Individuals are very distressed by their symptoms or their symptoms make them unable to function in social situations or at work.
A physical examination and sometimes tests are done to rule out other disorders that could cause the symptoms, including other mental health disorders, seizure disorders, and substance abuse.
Tests may include magnetic resonance imaging (MRI), computed tomography (CT), electroencephalography (EEG), and blood and urine tests to check for drugs.
Psychological tests and special structured interviews and questionnaires can also help medical professionals with the diagnosis.