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Reviewed/Revised Jan 2024
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What is schizophrenia?

Schizophrenia is a serious mental illness in which a person loses contact with reality (psychosis). A person with schizophrenia may have hallucinations (see or hear things that aren’t real) or believe unusual things that aren't true.

What causes schizophrenia?

Doctors think schizophrenia is caused by a problem with how the brain developed.

Doctors aren't sure exactly what causes the brain problem. However, schizophrenia is more likely if:

  • Other family members have it—it runs in families

  • A person had certain medical problems before or after birth, such as certain infections, not getting enough oxygen, or being underweight at birth

Schizophrenia isn't caused by poor parenting or a difficult childhood. However, bad and stressful things sometimes trigger schizophrenia in someone who's already at risk of it.

What are the symptoms of schizophrenia?

Schizophrenia may appear suddenly (in a few days or weeks) or slowly (over several years).

People with schizophrenia often have:

  • Delusions

  • Hallucinations

Delusions are beliefs that aren't true. But delusions in schizophrenia aren't like ordinary mistaken ideas. Lots of people believe things that others don't think are true. But in schizophrenia, people believe things even if there's strong evidence they're wrong or clearly unrealistic. For example, people may believe that:

  • Passages from books, newspapers, or song lyrics are talking about them

  • Others can read their mind, or their thoughts are being transmitted to others

  • People are out to get them

  • They are a famous person such as Jesus or the president

Hallucinations are hearing, seeing, tasting, or physically feeling things that aren’t there. Hearing voices is the most common hallucination. The voices often say mean things about the person or give orders.

Other symptoms of schizophrenia include:

  • Showing little or no emotion

  • Speaking very little, including answering questions in 1 to 2 words

  • Lack of interest in activities

  • Lack of interest in relationships with other people

  • Confused thinking

  • Rambling speech

  • Problems paying attention or remembering things

Schizophrenia isn't just unusual thinking and behavior. Schizophrenia causes symptoms severe enough to cause problems at home, at work, and with other people.

About 1 in 5 people with schizophrenia try to kill themselves, and many more have thought about it.

Although people with schizophrenia may have emotional outbursts and sometimes seem scary, they're only slightly more likely to be violent than other people.

How can doctors tell if someone has schizophrenia?

There's no test for schizophrenia. Doctors diagnose schizophrenia based on the person's symptoms. The symptoms have to be:

  • Present for at least 6 months

  • Cause problems in work, school, or relationships

Doctors may also do tests to check for other medical or drug problems that may be causing the behavior and need other types of treatment.

How do doctors treat schizophrenia?

The sooner treatment is started, the better a person usually does. Treatments include:

  • Medicines to treat symptoms

  • Talking regularly with a psychiatrist

  • Rehab and support programs to help people work, shop, care for themselves, manage a household, and get along with others

  • Counseling to help understand and cope with schizophrenia

  • Sometimes, treatment in the hospital

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