Schizophrenia is a chronic psychotic disorder that affects the way a person interacts with and understands the worldFootnote 1.

On this page


Key symptoms of active schizophrenia includeFootnote 1

The severity, duration and frequency of these symptoms can cause social and occupational challengesFootnote 2.


While there is no cure for schizophrenia, programs and treatments are available to help manage symptoms in the community and at work.

Reducing public misunderstanding and fear of the disease can reduce stigma and support affected individuals.Footnote 2

Risk factors

Although the exact cause of schizophrenia is unknown, it is recognized as a disorder of the brain with functional abnormality in brain circuits leading to symptomsFootnote 3. Of identified factors that may play a role in schizophrenia, genetics combined with lifestyle and environmental factors have been highlighted most. Risk of schizophrenia is higher in those individuals with family history of the disorderFootnote 4Footnote 5Footnote 6Footnote 7. Lifestyle and environmental factors that may contribute to the development of schizophrenia include prenatal or perinatal trauma, early life trauma, substance use among youth who have genetic vulnerability, or some baseline psychiatric symptomsFootnote 8Footnote 9Footnote 10Footnote 11Footnote 12Footnote 13Footnote 14Footnote 15Footnote 16Footnote 17.

Facts and figures

Knowledge development and exchange

Related links



Footnote 1

American Psychiatric Association. Schizophrenia spectrum and other psychotic disorders. In Diagnostic and statistical manual of mental disorders (5th ed.). 2013 (Retrieved November 2019)

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Footnote 2

Government of Canada. The human face of mental health and mental illness in Canada. 2006. (Retrieved January 2020)

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Footnote 3

Insel, T. R. Rethinking schizophrenia. Nature, 468(7321), 187-193. 2010

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Footnote 4

Kety, S. The significance of genetic factors in the etiology of schizophrenia: results from the national study of adoptees in Denmark. Journal of psychiatric research, 21(4), 423-429. 1987.

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Footnote 5

McGuffin, P., & Gottesman, I.I. Risk factors for schizophrenia. The New England Journal of Medicine, 341(5), 370. 1999.

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Footnote 6

McClellan, J., & King, M. Genetic heterogeneity in human disease. Cell, 141(2), 210-217. 2010.

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Footnote 7

Need, A., et al., A genome-wide investigation of SNPs and CNVs in schizophrenia. PLoS genetics. 5(2). 2009.

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Footnote 8

Susser, E.,& Lin, S. Schizophrenia after prenatal exposure to the Dutch Hunger Winter of 1944–1945. Archives of General Psychiatry 49, 983–988. 1992.

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Footnote 9

St Clair, D. et al. Rates of adult schizophrenia following prenatal exposure to the Chinese famine of 1959–1961. Journal of American Medical Association 294, 557–562. 2005.

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Footnote 10

Brown, A. & Derkits, E. Prenatal infection and schizophrenia: a review of epidemiologic and translational studies. American Journal of Psychiatry, 167, 261–280. 2010.

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Footnote 11

Cannon, M., Jones, P. & Murray, R. Obstetric complications and schizophrenia: historical and meta-analytic review. American Journal of Psychiatry, 159, 1080–1092. 2002.

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Footnote 12

Ellman, L. et al. Structural brain alterations in schizophrenia following fetal exposure to the inflammatory cytokine interleukin-8. Schizophrenia Research, 121, 46–54. 2010.

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Footnote 13

Nicodemus, K. et al. Serious obstetric complications interact with hypoxiaregulated/vascular-expression genes to influence schizophrenia risk. Molecular Psychiatry, 13, 873–877. 2008.

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Footnote 14

Feinberg, A. & Irizarry, R. Evolution in health and medicine Sackler colloquium: Stochastic epigenetic variation as a driving force of development, evolutionary adaptation, and disease. Proceedings of the National Academy of Sciences of the United States of America, 107 (suppl. 1), 1757–1764. 2010.

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Footnote 15

Barnes, T., Mutsatsa, S., Hutton, S., Watt, H., & Joyce, E. Comorbid substance use and age at onset of schizophrenia. The British Journal of Psychiatry188(3), 237-242. 2006.

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Footnote 16

Fowler, I., Carr, V., Carter, N., & Lewin, T. Patterns of current and lifetime substance use in schizophrenia. Schizophrenia bulletin24(3), 443-455. 1998.

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Footnote 17

Hartz, S. et al. Association between substance use disorder and polygenic liability to schizophrenia. Biological psychiatry82(10), 709-715. 2017.

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