While there’s no single test for diagnosing schizophrenia, mental health professionals can diagnose schizophrenia in a number of ways.
Schizophrenia is a chronic, disabling psychiatric condition that causes symptoms like hallucinations and delusions. Early diagnosis and treatment are very important for managing symptoms before major complications arise and for a better long-term prognosis.
But diagnosing schizophrenia can be challenging for several reasons.
No single test can diagnose schizophrenia. Instead, it’s diagnosed by evaluating a person’s symptoms over several months and ruling out other possible health conditions. Use of certain drugs like methamphetamine or LSD can cause symptoms resembling schizophrenia. Schizophrenia also can have similar symptoms to other psychiatric conditions, such as bipolar disorder. This can result in misdiagnosis and inappropriate treatment in some cases.
Diagnosing and treating schizophrenia is further complicated by the fact that many with schizophrenia aren’t aware they have it. This symptom, called anosognosia or “lack of insight,” can make helping people with the condition more difficult.
Factors like these can lead to delays in proper diagnosis and treatment, which can cause worsened symptoms, physical health problems, or early death. But a timely and correct diagnosis significantly boosts a person’s odds of managing their symptoms and recovering.
Schizophrenia is usually diagnosed by a mental health professional, such as a psychiatrist.
The condition usually follows a progression. Schizophrenia often starts with a prodrome, or early, mild symptoms indicating the onset of the condition, such as changes in behavior including cognitive difficulties, social withdrawal, paranoid or suspicious thoughts, or sleep disturbances. A diagnosis is usually made once the condition progresses to first-episode psychosis, a symptom of schizophrenia that involves hallucinations (seeing or hearing things that aren’t there) and delusions (steadfast false beliefs that are clearly untrue to everyone around them).
Getting a correct schizophrenia diagnosis typically involves the following steps:
Mental Health Evaluation
Your healthcare provider will perform a mental health evaluation to assess your symptoms. They do this by asking you or your loved ones questions about your health, observing your behavior, and noting your reported symptoms. Some of their questions will be aimed at ruling out other conditions that could be causing your symptoms. They will then compare this information to established criteria for a schizophrenia diagnosis.
The criteria are outlined in the Diagnostic and Statistical Manual of Disorders, Fifth Edition (DSM-5), which is a guide used by professionals to diagnose mental health conditions. The criteria needed to be diagnosed with schizophrenia are:
You have at least two of the five main symptoms of schizophrenia.
You’ve had symptoms for one month or more.
Your symptoms affect your ability to work or maintain relationships.
Delusions Strongly held false beliefs that are clearly untrue, such as believing that someone is controlling your thoughts.
Hallucinations Seeing, smelling, hearing, feeling, or tasting things that don’t actually exist. This can include hearing voices, for example.
Disorganized or Incoherent Speech Having problems organizing your thoughts when you speak, making it difficult for others to understand what you are saying.
Disorganized or Unusual Movements You move in ways that are unusual to others, such as moving excessively for no apparent reason or not moving much at all.
Negative Symptoms Negative symptoms refer to the absence of expected ways of interacting with your surroundings. Examples include having little facial expression or speaking without any emotion in your voice.
Physical Evaluation
A physical exam for schizophrenia includes assessing your general appearance, such as hygiene and grooming. This gives your doctor a picture of your self-care habits. It also includes obtaining a set of vital signs, such as blood pressure and heart rate, to screen for any underlying health problems.
Your doctor may also take your height, weight, and body mass index (BMI) as part of your physical examination.
Lab Tests and Screenings
Your mental health provider may also order laboratory or imaging tests to help rule out other conditions with similar symptoms. These tests may include:
Drug and Alcohol Screening This helps confirm or rule out the use of alcohol or drugs like LSD or methamphetamines, which can cause schizophrenia-like symptoms.
Blood Tests Blood tests help assess your kidney function, liver function, electrolyte levels, and other clinical data.
Magnetic Resonance Imaging (MRI) or Computerized Tomography (CT) These imaging scans are used to gather detailed images of the brain.
As mentioned, healthcare providers need to rule out other conditions that can cause symptoms resembling schizophrenia. These include:
Schizoaffective DisorderSchizoaffective disorder is a psychiatric condition that shares some symptoms of schizophrenia, such as delusions and hallucinations, but also involves mood symptoms, such as mania or depression.
Bipolar Disorder With Psychotic Features Bipolar disorder is a mood disorder involving alternating manic, hypomanic, or depressive mood episodes (periods of intense emotional states). Like schizophrenia, bipolar disorder can also involve episodes of psychosis.
Major Depressive Disorder With Psychotic Features Major depressive disorder (aka depression) is a mood disorder involving persistent depressed mood, loss of interest or pleasure in activities once enjoyed, and other symptoms. In some cases, major depressive disorder can involve episodes of psychosis.
Delusional Disorder Delusional disorder is a psychiatric condition that involves delusions, but doesn’t involve other typical symptoms of schizophrenia like hallucinations or disorganized speech.
Substance-Induced Psychotic Disorder Substance-induced psychotic disorder is a form of psychosis caused by starting or stopping drug or alcohol use, especially during periods of intoxication or withdrawal. As mentioned, using drugs such as methamphetamines or LSD can cause symptoms similar to schizophrenia. Methamphetamine use can cause hallucinations and paranoia. LSD can cause hallucinations and a disconnect from reality.
Diagnosing schizophrenia can be challenging, as its symptoms can resemble those of other mental health conditions, and many with schizophrenia aren’t aware they have it.
Delays in diagnosis can lead to worsened symptoms, physical health issues, or early death, but early diagnosis and treatment can improve prognosis.
A physical exam, mental health exam, lab tests, and sometimes imaging tests are needed to get an accurate diagnosis.
