is a mental disorder characterized by abnormal social behavior and failure to understand what is real. Common symptoms include false beliefs, unclear or confused thinking, hearing voices that others do not, reduced social engagement and emotional expression, and a lack of motivation. People with schizophrenia often have additional mental health
problems such as anxiety
disorders, major depressive illness, or substance use disorders. Symptoms typically come on gradually, begin in young adulthood, and last a long time.
The causes of schizophrenia include environmental and genetic factors. Possible environmental factors
include being raised in a city, cannabis use, certain infections, parental age, and poor nutrition during pregnancy
. Genetic factors include a variety of common and rare genetic variants. Diagnosis is based on observed behavior, the person's reported experiences, and reports of others familiar with the person. During diagnosis a person's culture must also be taken into account. As of 2013 there is no objective test. Schizophrenia does not imply a "split personality
" or "multiple personality disorder"—conditions with which it is often confused in public perception.
The mainstay of treatment is antipsychotic medication, along with counselling, job training, and social rehabilitation. It is unclear whether typical or atypical antipsychotics are better. In those who do not improve with other antipsychotics clozapine may be tried. In more serious situations—where there is risk to self or others—involuntary hospitalization
may be necessary, although hospital
stays are now shorter and less frequent than they once were.
About 0.3–0.7% of people are affected by schizophrenia during their lifetimes. In 2013 there were estimated to be 23.6 million cases globally. Males are more often affected than females. About 20% of people do well, and a few recover completely. Social problems, such as long-term unemployment, poverty, and homelessness are common. The average life expectancy
of people with the disorder is ten to twenty-five years less than for the general population. This is the result of increased physical health problems and a higher suicide rate (about 5%). In 2013 an estimated 16,000 people worldwide died from behavior related to, or caused by, schizophrenia.