What is schizophrenia?
Schizophrenia is a type of mental illness known as a "psychosis." A psychosis is a mental illness in which a person cannot tell what is real from what is imagined. At times, people with psychotic illnesses lose touch with reality. The world may seem like a jumble of confusing thoughts, images, and sounds.
How common is schizophrenia?
Schizophrenia is more common than most people think. About 1 in 200 of the people in the United States will develop schizophrenia over the course of their lives. It's also important to know that schizophrenia has many different symptoms and can show up in many different ways.
Schizophrenia is not the same as a "split personality." A split personality is another type of mental illness. Split personality is much less common than schizophrenia.
Who gets schizophrenia?
Anyone can get schizophrenia. In men, psychotic symptoms often begin in the teens or 20s. In women, psychotic symptoms often begin in the 20s and 30s.A person is not considered to have schizophrenia unless symptoms last for at least six months.
What is "paranoid schizophrenia?"
Paranoid schizophrenia is one type of schizophrenia. In this type, the person's false beliefs are mainly about being persecuted or being punished by someone. The person may hear the voice of someone he or she believes is punishing them. The person may believe that he or she has been specially chosen to complete a secret mission. These are just a few examples of any number of false beliefs a person with this disorder may have.
Other types of schizophrenia include "catatonic" schizophrenia and "disorganized" schizophrenia. Different types of schizophrenia may have some of the same symptoms.
Symptoms and Causes
What causes schizophrenia?
There's no one cause for schizophrenia. It does not happen because of poor parenting or a bad upbringing. Although stress can trigger or worsen symptoms, stress does not cause schizophrenia. Schizophrenia is a disorder of the brain. It most likely develops from a mix of factors that may include:
- A defect in certain chemicals in the brain that control thinking and understanding.
- The person's genetic make-up (A likelihood for getting schizophrenia may be passed on to children by parents.)
- A defect in how the brain forms a person's personality.
What kind of symptoms might people with schizophrenia have?
People with schizophrenia may have a number of psychotic symptoms. These symptoms can come and go in phases, or they can happen only once or twice in a lifetime. When the illness begins, psychotic symptoms are usually sudden and severe.
During psychotic phases, the person may still understand parts of reality. He or she may lead a somewhat normal life, doing basic activities such as eating, working and getting around. In other cases, the person may be unable to function. Symptoms during psychotic phases include:
- Seeing, hearing, feeling or smelling things that are not real (called hallucinations).
- Having strange beliefs that are not based on facts (called false beliefs or delusions). For example, the person may believe that people can hear his or her thoughts, that he or she is God or the devil, or that people are putting thoughts into his or her head.
- Thinking in a confused way, being unable to make order out of the world, shifting quickly from one thought to the next.
- Having emotions, thoughts and moods that do not fit with events.
People with schizophrenia also may:
- Have a lot of energy or be overly active, or become "catatonic," a state in which the body becomes rigid and cannot be moved.
- Talk in sentences that do not make sense.
- Not wash or groom.
- Cut themselves off from family, friends and the outside world.
- Be unable to function in school, work, or other activities.
- Lose interest in life.
- Behave in strange ways.
- Be very sad (depressed) or have mood swings.
- Have dulled emotions.
- Be inactive.
Diagnosis and Tests
How is schizophrenia diagnosed?
If symptoms are present, your doctor will perform a complete medical history and physical examination. Although there are no laboratory tests to specifically diagnose schizophrenia, the doctor might use various diagnostic tests — such as MRI or CT scans or blood tests — to rule out physical illness as the cause of your symptoms.
If the doctor finds no physical reason for the symptoms, he or she might refer the person to a psychiatrist or psychologist, healthcare professionals who are specially trained to diagnose and treat mental illnesses. Psychiatrists and psychologists use specially designed interview and assessment tools to evaluate a person for schizophrenia. The doctor or therapist bases his or her diagnosis on the person’s report of symptoms, and his or her observation of the person’s attitude and behavior.
The doctor or therapist then determines if the person’s symptoms point to a specific disorder as outlined in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5), which is published by the American Psychiatric Association and is the standard reference book for recognized mental illnesses. According to the DSM-5, a diagnosis of schizophrenia is made if a person has two or more core symptoms, one of which must be hallucinations, delusions, or disorganized speech for at least one month. The other core symptoms are gross disorganization and diminished emotional expression. Other DSM-5 criteria for a diagnosis of schizophrenia include:
- Level of work, interpersoanl relations or self-care is significantly below what it was before the start of symptoms.
- Signs of disturbance that have lasted at least 6 months.
- Schizoaffective disorder and depressive or bipolar disorder with psychotic symptoms have been ruled out.
- The disturbance is not caused by substance abuse or another medical condition.
Management and Treatment
Can schizophrenia be treated?
Yes. The main types of treatment are counseling and medicines to lessen or stop psychotic symptoms. Medicines will control psychotic symptoms in most people. In milder cases of schizophrenia, medications may not be needed. Medicines can:
- Lessen or stop hallucinations
- Help the person tell the difference between hallucinations and the real world
- Lessen or stop false beliefs
- Lessen feelings of confusion
- Help the person think more clearly
Lessening of these symptoms can help the person resume his or her normal lifestyle and activities. Medicines for schizophrenia need to be taken regularly, even after symptoms are gone. Some people with schizophrenia will stop taking their medicine because they believe the medicine is no longer needed, or they dislike the medication's side effects. Psychotic symptoms often return when medication is stopped. Do not stop taking medicine without the advice of your healthcare provider.
Discuss any concerns you have about side effects with your healthcare provider.
Where can I learn more?
For more information, contact the following organizations:
- National Alliance for the Mentally Ill: 800.950.6264
- Brain and Behavior Research Foundation: 800.829.8289
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