About schizophrenia

About schizophrenia 

  • Schizophrenia is a complex psychiatric disorder1 comprising of a range of symptoms including positive symptoms, such as hallucinations and delusions,2,3 and negative symptoms, such as social withdrawal and apathy.4,5

  • Schizophrenia is often a persistent mental illness, with those afflicted experiencing distorted thinking, emotions, language, behaviour and a sense of self.1,6

  • Schizophrenia is considered our nation’s most disabling, and heavily stigmatised mental illness.7

  • Those living with schizophrenia may at times, lose touch with reality.6

  • Schizophrenia can affect a person’s ability to function at school or at work, and in personal relationships.8

  • Schizophrenia is considered one of the most severe mental disorders due to its very high associated death rates.9

  • The average life expectancy of someone living with schizophrenia is 20 years below that of the general population.9 This is often attributed to preventable physical diseases, such as heart disease, diabetes and infections, and also due to a high rate of suicide among the patient population.10,11

  • The annual cost to Australian society of psychosis (one of the main symptoms of schizophrenia)6 is an estimated AUD 6 billion. However this figure does not account for the pain endured by individuals, their families, and the supporting community.12


  • Prevalence is estimated globally at about 0.4 per cent, equating to approximately 90,000 Australians.12

  • Schizophrenia typically presents in late adolescence, with two in three people experiencing their first episode before the age of 25.13,14

  • Although men and women have an equal chance of developing schizophrenia, men often show symptoms at a younger age, compared to women.13,15

  • Between 20 to 30 per cent of those living with schizophrenia experience only a few brief episodes. For others however, it is a chronic disorder, with 40 per cent experiencing recurrent, short episodes, and 35 per cent remaining disabled long-term.1,16



  • While the causes of schizophrenia are not completely understood, genetics is considered the most important risk factor for developing the mental disorder.2,8   

  • No single gene has yet to be identified as responsible for causing schizophrenia. Rather, a number of genes combined may increase an individual’s risk.8

  • If one parent has schizophrenia, their child/children has a 10 per cent chance of developing the disorder.15

  • Complex interactions between aspects of a person’s environment and genetics may play a role in the development of schizophrenia.4 

  • Environmental factors may include living in poverty, stressful surroundings, birth complications or nutritional problems prior to birth, and exposure to certain viruses.4,8

  • Stressful incidents can trigger symptoms of schizophrenia, including exposure to violence and trauma.8,15

  • A chemical imbalance involving the neurotransmitter, dopamine, found in the brain, is also thought to be involved in schizophrenia. However this imbalance does not completely explain why some people develop schizophrenia.2,15

  • Illicit drug use, particularly cannabis and amphetamines, is believed to trigger psychosis in those who may be vulnerable to developing schizophrenia.15

Symptoms – positive, negative & cognitive

  • Schizophrenia symptoms can be categorised into three domains – positive, negative and cognitive symptoms.2,17

  • Negative symptoms of schizophrenia are characterised by the absence, or reduction of normal behaviour and function.5 

  • Negative symptoms, including reduced emotion and motivation, can lead to difficulty starting, and sustaining activities and tasks, diminished feelings of pleasure in everyday life, and social withdrawal.4,5

  • Negative symptoms are associated with long-term illness, significant social and economic costs, and high levels of unemployment. Higher severity of negative symptoms are related to a lower quality of life.18 

  • On the other hand, positive symptoms of schizophrenia refer to the presence (rather than absence) of symptoms and are experienced in addition to reality.19,20

  • Positive symptoms are the most recognisable symptoms of schizophrenia, and indicate that a person has lost touch with reality. They include hallucinations, voices that converse with, or about the patient, and delusions that are often paranoid.2,3 

  •  One of the main symptoms of schizophrenia is psychosis, during which a person finds it hard to distinguish between what is, and isn’t real.6

  • Psychosis is often experienced in short episodes of intense symptoms. Symptoms of psychosis include:4,6,21

    • Delusions – firmly held beliefs which are not supported by objective facts. Delusions may include paranoia that others are ‘out to get you’, or that special messages requiring a response are being broadcast over the television, radio or internet.

    • Hallucinations – such as hearing voices or seeing things that don’t exist.

    • Disorganised thinking – thoughts and speech that is unusual and disrupted. 

    • Disorganised behaviour – inappropriate or bizarre behaviour, actions or gestures. Inappropriate behaviour also involves exhibiting incorrect emotional responses within a given context.

  • Cognitive symptoms of schizophrenia include difficulty expressing one’s thoughts and deficits in memory, problem solving skills, concentration and attention.17

  • Cognitive symptoms often begin before symptoms of psychosis, in those living with schizophrenia.17

  •  These symptoms are linked to a decline in employment, independent living and functioning  socially and within the community.22


  •  Schizophrenia can take time to diagnose, given a person must experience one month of psychotic symptoms and at least six months of difficulties in important areas of their life, such as work, relationships and self-care, before a diagnosis is confirmed.6

  •  GPs generally perform an initial assessment of a person before referring them to a specialist, usually a psychiatrist, for full diagnosis and treatment.6

  • During the initial assessment, the GP may perform a mental health interview, by asking questions pertaining to the person’s current symptoms, mental health history, family history, and to determine whether the signs and symptoms are due to substance abuse.2,8

  • The GP will then perform a physical examination, and possibly order blood tests or a brain scan, to rule out any underlying causes.8

Stigma & misconceptions about schizophrenia

  •  People living with schizophrenia often experience stigma in the community, and are vulnerable to human rights violations in mental health institutions and communities.11

  • One of the biggest myths surrounding schizophrenia is that those living with the mental disorder have a ‘split personality’ or ‘multiple personalities’, which is not the case.1,16 

  • Another misconception is that schizophrenia is often associated with violent and erratic behaviour.1 

  • Only a minority of people living with schizophrenia become aggressive when experiencing an untreated, acute episode, which is generally due to their hallucinations or delusions.16

  • Stigma can contribute to the onset of psychosis in schizophrenia, delays in accessing treatment, social isolation,  stress, and furthermore, places those affected at higher risk for a more severe course of illness.23

Psychological impact & quality of life

  • The impact schizophrenia has on one’s life depends on the symptoms, severity and pattern of illness over time, in addition to the treatment and social support they receive.13,24 

  • Many people living with schizophrenia experience high rates of unemployment, low income, and poor physical health.25

  • Approximately one in four people living with schizophrenia meet the criteria for ‘depressive disorder’ at some stage in their lives.25

  • Feelings of hopelessness and demoralisation are indicators for increased risk of suicide, as well as feelings of social isolation.25

  • People living with schizophrenia, especially those who experience negative symptoms, often lack motivation for day-to-day activities.1

  • Tragically, approximately one in 10 people living with schizophrenia commit suicide.

  • Studies reveal the quality of life is better for those living with schizophrenia who are integrated into community support programs, compared with those who are institutionalised.24


  • The most common form of pharmacological treatment for schizophrenia is antipsychotic medication.2,8

  • High levels of dopamine in the brain may cause symptoms of psychosis. Antipsychotic medications work by reducing the levels of dopamine in the brain, or by restoring the balance of dopamine with other chemicals in the brain.26

  • Relapses often occur in schizophrenia, with each additional relapse resulting in worsening of symptoms, cognitive decline, reduced social and employment abilities, and quality of life.27

  • Management should also include community support programs to provide those living with schizophrenia appropriate information, assistance with finding suitable work, training and education, psychosocial rehabilitation and support groups.28

Seqirus™(Australia) Pty Ltd. ABN 66 120 398 067. Melbourne, Victoria. Seqirus Medical Information: 1800 642 865. Seqirus™ is a trademark of Seqirus UK limited or its affiliates. Date of Preparation: August 2021. ANZ-NOPR-21-0001.


  1. Better Health Channel. Schizophrenia.  [June 2021]; Available from:

  2. Schultz, S.H., S.W. North, and C.G. Shields, Schizophrenia: a review. Am Fam Physician, 2007. 75(12): p. 1821-9.

  3. NeuRA. Positive symptoms. 2020  [June 2021]; Available from:

  4. 4.    National Institute of Mental Health. Schizophrenia. 2020  [June 2021]; Available from:

  5. NeuRA. Negative symptoms. 2020  [July 2021]; Available from:

  6. SANE Australia. Schizophrenia. 2017  [June 2021]; Available from:

  7. Australian Goverment Productivity Commission, Mental Health, Productivity Commission Inquiry Report. 2020.

  8. Health Direct. Schizophrenia. 2020  [June 2021]; Available from:

  9.  Laursen, T.M., M. Nordentoft, and P.B. Mortensen, Excess early mortality in schizophrenia. Annu Rev Clin Psychol, 2014. 10: p. 425-48.

  10. Wildgust, H.J., R. Hodgson, and M. Beary, The paradox of premature mortality in schizophrenia: new research questions. J Psychopharmacol, 2010. 24(4 Suppl): p. 9-15.

  11. World Health Organization (WHO). Schizophrenia. 2019  [June 2021]; Available from:

  12. The Royal Australian & New Zealand College of Psychiatrists, The economic cost of serious mental illness and comorbidities in Australia and New Zealand. . 2016.

  13. Your Health in Mind. Schizophrenia. 2017  [June 2021]; Available from:

  14. Garvan Institute of Medical Research. Schizophrenia.  [cited July, 2021; Available from:

  15. Australian Government Department of Health. What causes schizophrenia? 2007  [June 2021]; Available from:

  16. Queensland Health. Queesnland MIND essentials - Schizophrenia.  [June 2021]; Available from:

  17. Bowie, C.R. and P.D. Harvey, Cognitive deficits and functional outcome in schizophrenia. Neuropsychiatric disease and treatment, 2006. 2(4): p. 531-536.

  18. Rudnick, A., The impact of coping on the relation between symptoms and quality of life in schizophrenia. Psychiatry, 2001. 64(4): p. 304-8.

  19. American Psychological Association. APA Dictionary of Psychology - positive symptom. [June 2021]; Available from:

  20. Rethink Mental Illness. Schizophrenia.  [July 2021]; Available from:

  21. NeuRA. Disorganised symptoms. 2020  [June 2021]; Available from:

  22. Tripathi, A., S.K. Kar, and R. Shukla, Cognitive Deficits in Schizophrenia: Understanding the Biological Correlates and Remediation Strategies. Clin Psychopharmacol Neurosci, 2018. 16(1): p. 7-17.

  23. Gil Dov Hoftman, M.D., Ph.D., The Burden of Mental Illness Beyond Clinical Symptoms: Impact of Stigma on the Onset and Course of Schizophrenia Spectrum Disorders. American Journal of Psychiatry Residents' Journal, 2016. 11(4): p. 5-7.

  24. Pîrlog, M.C., et al., Quality of Life-a Goal for Schizophrenia's Therapy. Current health sciences journal, 2018. 44(2): p. 122-128.

  25. Bosanac, P. and D.J. Castle, Schizophrenia and depression. Med J Aust, 2013. 199(S6): p. S36-9.

  26. Better Health Channel. Antipsychotic medications.  [June 2021]; Available from:

  27. Olivares, J.M., et al., Definitions and drivers of relapse in patients with schizophrenia: a systematic literature review. Ann Gen Psychiatry, 2013. 12(1): p. 32.

  28. Mental Illness Fellowship of Australia. Schizophrenia. [June 2021]; Available from: