What is schizophrenia?

Schizophrenia is a severe and chronic mental health disorder that can be disabling and affects how someone thinks, feels and behaves. Commonly, people with this illness appear to lose touch with reality.

What are the symptoms of schizophrenia?

Signs of schizophrenia are divided into three categories: positive, negative and cognitive symptoms. Positive symptoms are psychotic behaviors not generally seen in healthy people. Those with the illness may lose touch with reality and experience hallucinations, delusions, unusual or dysfunctional ways of thinking and agitated body movements.

People with negative symptoms of schizophrenia may suffer emotional and behavioral disruptions that result in their facial expressions or tone of voice becoming flat and lifeless. In addition, those with the illness may stop feeling pleasure in everyday life, find it hard to start and sustain activities, and speak much less often.

Additionally, the cognitive symptoms of this mental illness may be subtle for some and more severe for others. People find themselves unable to understand information, make decisions, focus and pay attention, or they may have problems using their “working memory” (difficulty putting things they’ve just learned into practice).


What causes schizophrenia?

Reasons some people may develop schizophrenia include the following:

  • Genes and environment. Scientists believe many different genes may increase someone’s risk of developing schizophrenia. That said, the illness may develop in people who have no family members with the disorder; some may have family members with the disorder but don’t develop it themselves. Environmental factors that may contribute to the development of schizophrenia include exposure to viruses, malnutrition before birth, problems during birth and psychosocial factors associated with physical health, such as stress, hostility, depression, hopelessness and lack of job control.
  • Different brain chemistry and structure. Many researchers think that an imbalance in chemical reactions involving neurotransmitters—substances used by brain cells to communicate with one another—may play a role in schizophrenia.
  • Environment. According to the National Alliance on Mental Illness (NAMI), exposure to viruses or malnutrition before birth, particularly in the first and second trimesters has been shown to increase the risk of schizophrenia. Inflammation or autoimmune diseases can also lead to increased immune system
  • Substance use. Some studies have suggested that taking mind-altering drugs during teen years and young adulthood can increase the risk of schizophrenia, says NAMI. A growing body of evidence indicates that smoking marijuana increases the risk of psychotic incidents and the risk of ongoing psychotic experiences. The younger and more frequent the use, the greater the risk. 

How is schizophrenia diagnosed?

As there’s no lab test that can diagnose schizophrenia, doctors find the illness hard to pinpoint. This is why health care providers evaluate someone’s symptoms during a period of six months. To confirm a diagnosis, doctors must rule out other factors, such as brain tumors, possible medical conditions, bipolar disorder and other psychiatric problems.

In order to diagnose someone with schizophrenia, doctors must determine whether someone is suffering from two or more of the following symptoms: delusions, hallucinations, disorganized speech, disorganized or catatonic behavior and other negative symptoms.

How is schizophrenia treated?

Currently, schizophrenia isn’t curable, but physicians can treat and manage the disorder with antipsychotic medications. They may also use psychosocial therapies to teach those with the illness coping skills that enable them to go to school and work.

Additionally, coordinated specialty care is a treatment model aimed at reducing symptoms and improving the quality of life for people living with schizophrenia. This kind of therapy integrates medication, psychosocial therapies, social work family involvement, supportive education and employment programs to help people with the disorder lead productive, independent lives.

Last Reviewed: February 28, 2019