Schizophrenia
Peer reviewed by Dr Doug McKechnie, MRCGPLast updated by Dr Colin Tidy, MRCGPLast updated 9 Sept 2024
Meets Patient’s editorial guidelines
- DownloadDownload
- Share
In this series:PsychosisAntipsychotic medicines
Schizophrenia is a mental disorder. Symptoms include hearing, seeing, smelling or tasting things that are not real (hallucinations); false ideas (delusions); disordered thoughts and problems with feelings, behaviour and motivation.
The cause is not clear. In many people symptoms come back (recur) or persist long-term but some people have just one episode of symptoms that lasts a few weeks. Treatment includes medication, talking treatments and social support.
In this article:
Continue reading below
What is schizophrenia?
What is schizophrenia?
Schizophrenia is a serious mental health condition that causes disordered ideas, beliefs and experiences. In a sense, people with schizophrenia lose touch with reality and do not know which thoughts and experiences are real and which are not.
Some people misunderstand schizophrenia. For instance, it has nothing to do with a split personality. Also, the vast majority of people with schizophrenia are not violent.
Patient picks for Other mental health problems
Mental health
How borderline personality disorder affects your life
Borderline personality disorder (BPD) - also called emotionally unstable personality disorder - is a mood condition that can affect how someone interacts with other people. Yet despite BPD affecting an estimated one in 100 people, according to the charity Rethink Mental Illness, it is still commonly misunderstood. People with BPD may struggle with the way they think and feel about themselves and other people, which can impact many aspects of their lives.
by Lydia Smith
Mental health
Avoidant personality disorder
Personality refers to our way of behaving, experiencing life, and how we see and interpret ourselves, other people, events, and situations. A personality disorder is a disturbance in how we function mentally as a person, which leads to considerable personal and social disruption.
by Dr Colin Tidy, MRCGP
Types of schizophrenia
Schizophrenia used to be divided into 5 sub-types. These were called: paranoid, disorganised (hebephrenic), catatonic, undifferentiated and residual. But this classification is no longer used as it was found to be unhelpful and unreliable, because lots of symptoms overlapped between the different sub-types.
Continue reading below
How common is schizophrenia?
Schizophrenia develops in about 1 in 100 people. It can occur in men and in women. The most common ages for it first to develop are aged 15-25 in men and aged 25-35 in women.
Schizophrenia symptoms
People diagnosed with schizophrenia may display a range of symptoms. Mental health professionals often class the symptoms as 'positive' and 'negative'.
Positive symptoms are those that show abnormal mental functions. Negative symptoms are those that show the absence of a mental function that should normally be present.
Positive schizophrenia symptoms
These are sometimes referred to as psychotic symptoms. These include:
Delusions. These are false beliefs that a person has and most people from the same culture would agree that they are wrong. Even when the wrongness of the belief is explained, a person with schizophrenia is convinced that they are true. For example, a person with schizophrenia may believe such things as:
Neighbours are spying on them with cameras in every room; or
A famous person is in love with them; or
People are plotting to kill them; or
There is a conspiracy about them.
These are only a few examples and delusions can be about anything.
Hallucinations. This means hearing, seeing, feeling, smelling, or tasting things that are not actually there. Hearing voices is the most common. Some people with schizophrenia hear voices that provide a running commentary on their actions, argue with them, or repeat their thoughts. The voices often say things that are rude, aggressive, and unpleasant, or give orders that must be followed. Some people with schizophrenia appear to talk to themselves as they respond to the voices. People with schizophrenia believe that the hallucinations are real.
Disordered thoughts. Thoughts may become jumbled or blocked. Thought and speech may not follow a normal logical pattern. For example, some people with schizophrenia have one or more of the following:
Thought echo: this means the person hears his or her own thoughts as if they were being spoken aloud.
Knight's-move thinking: this means the person moves from one train of thought to another that has no apparent connection to the first.
Some people with schizophrenia may invent new words (neologisms), repeat a single word or phrase out of context (verbal stereotypy), or use ordinary words to which they attribute a different, special meaning (metonyms).
Symptoms called disorders of thought possession may also occur. These include:Thought insertion: the person believes that the thoughts in their mind are not their own and that they are being put there by someone else.
Thought withdrawal: the person believes that their thoughts are being removed from their mind by an outside agency.
Thought broadcasting: the person believes that their thoughts are being read or heard by others.
Thought blocking: the person experiences a sudden interruption of the train of thought before it is completed, leaving a blank. The person suddenly stops talking and cannot recall what he or she has been saying.
Negative schizophrenia symptoms
These include:
Lack of motivation. Everything seems an effort - for example, tasks may not be finished, concentration is poor, there is loss of interest in social interaction and the person often wants to be alone.
Few spontaneous movements and much time doing nothing.
Facial expressions do not change much and the voice may sound monotonous.
Changed feelings. Emotions may become flat. Sometimes the emotions may be odd, such as laughing at something sad. Other strange behaviours sometimes occur.
Negative symptoms of schizophrenia may make some people neglect themselves. They may not care to do anything and appear to be wrapped up in their own thoughts. Negative symptoms can also lead to difficulty with education, which can contribute to difficulties with employment. For families and carers, the negative symptoms are often the most difficult to deal with. Persistent negative symptoms tend to be the main cause of long-term disability.
Families may only realise with hindsight that the behaviour of a relative has been gradually changing. Recognising these changes can be particularly difficult if the illness develops during the teenage years when it is normal for some changes in behaviour to occur.
Other symptoms
Other symptoms that occur in some cases include difficulty planning, memory problems and obsessive-compulsive symptoms.
Continue reading below
What causes schizophrenia?
The cause is not known for certain but it is believed to be linked to genetic and environmental factors. It is thought that the balance of brain chemicals (neurotransmitters) is altered. Neurotransmitters are needed to pass messages between brain cells. An altered balance of these may cause the symptoms. It is not clear why changes occur in the neurotransmitters.
Studies have shown very slight differences in brain structure in some people with schizophrenia. Scientists think that this means that differences in brain development may be a factor in schizophrenia.
Is schizophrenia genetic?
Inherited (genetic) factors are thought to be important. For example, a close family member (child, brother, sister, parent) of someone with schizophrenia has a 1 in 10 chance of also developing the condition. This is 10 times the normal chance. A child born to a mother and father who both have schizophrenia has a higher risk of developing it but one or more factors appear to be needed to trigger the condition in people who are genetically prone to it.
Risk factors
Risk factors for schizophrenia may include:
Stress such as relationship problems, financial difficulties, social isolation, bereavement, etc.
A viral infection during the mother's pregnancy, or in early childhood.
A lack of oxygen at the time of birth that may damage a part of the brain.
Recreational drugs may trigger the condition in some people. For example, heavy cannabis usage may account for between 8% and 14% of schizophrenia cases. Many other recreational drugs such as amphetamines, cocaine, ketamine and lysergic acid diethylamide (LSD) can trigger a schizophrenia-like illness.
Diagnosing schizophrenia
Schizophrenia tests
Blood and urine tests may be done. This will rule out physical causes of the symptoms or drug/alcohol misuse which may cause similar symptoms. People already diagnosed with schizophrenia may also have tests done if they suddenly become worse.
Neuroimaging (CT or MRI) may be done if there are other features suggestive of a physical intracranial cause, such as abnormal behaviour following a head injury.
How is the diagnosis made?
Some of the symptoms and signs of schizophrenia also occur in other mental health conditions such as:
Postpartum psychosis (puerperal psychosis or postnatal psychosis), which occurs in mothers in the days or weeks following childbirth.
Schizoaffective disorder, which presents with mixed features of mood disorders (eg, bipolar disorder) and schizophrenia.
After taking some recreational drugs.
Therefore, the diagnosis may not be clear at first and it may take time to differentiate schizophrenia from another type of psychotic disorder.
Not all symptoms are present in all cases. Different forms of schizophrenia occur depending upon the main symptoms that develop.
Sometimes the symptoms and signs of schizophrenia develop quickly over a few weeks or so. Family and friends may recognise that the person has a mental health problem. Sometimes symptoms develop slowly over months and the person may gradually become withdrawn, lose friends, jobs, etc, before the condition is recognised.
In the past, schizophrenia has been classified into subtypes, depending on the most predominant symptoms and signs of any individual person with schizophrenia. These subtypes are no longer used because there is a great deal of variation of symptoms for people with schizophrenia. Examples of these subtypes include:
Paranoid schizophrenia
For example, people with paranoid schizophrenia mainly have positive symptoms which include delusions that people are trying to harm them.
Simple schizophrenia
In contrast, some people mainly have negative symptoms and this is described as simple schizophrenia. In many cases there is a mix of positive and negative symptoms.
Catatonic schizophrenia
Catatonic schizophrenia is used to describe a state of catatonia in addition to schizophrenia. Catatonia is a state in which someone is awake but does not seem to respond to other people and their environment. Catatonia can affect someone’s movement, speech and behaviour in many different ways.
Catatonic schizophrenia is much rarer than it used to be. It used to be seen more commonly in untreated schizophrenia, but is rare now that there are much better treatments.
Disorganised schizophrenia
The term disorganised schizophrenia (or hebephrenic schizophrenia) has been used to describe prominent characteristics of disorganised behaviour and speech, and flat or inappropriate affect (lack of emotion or expression).
Schizophrenia treatment
Treating schizophrenia usually involves a combination of medication, therapy, encouraging a healthy lifestyle, including avoiding recreational drug usage, and self-management techniques, in addition to family and social services support as needed. These treatment options include:
Antipsychotic medication
The main medicines used to treat schizophrenia are called antipsychotics. They work by altering the balance of some brain chemicals (neurotransmitters).
Psychological treatments
Cognitive behavioural therapy (CBT)
Psychological treatments include a variety of talking treatments, in particular CBT. CBT is used as a treatment for various mental health conditions, including schizophrenia.
Family intervention
This may be offered and consists of about 10 therapy sessions for relatives of patients with schizophrenia. It has been found to reduce hospital admissions and the severity of symptoms for up to two years after treatment.
Art therapy
This has been found to be helpful, particularly for negative symptoms.
Social and community support
This is very important. Often the key worker plays a vital role. However, families, friends and local support groups can also be major sources of help. Support organisations have many local groups throughout the UK. Examples include Mind and the Hearing Voices Network. See below for contact details.
Encouraging physical health
It is quite common for people with schizophrenia not to look after themselves so well. Such things as smoking, lack of exercise, obesity and an unhealthy diet are more common than average in people with schizophrenia. Weight gain may be a side-effect of antipsychotic medicines. All these factors may lead to an increased chance of developing heart disease and diabetes in later life.
Therefore, as with everyone else in the population, people with schizophrenia are encouraged to adopt a healthy lifestyle. Advice includes:
To take regular exercise.
To eat healthily.
Community based treatment
Treatment and care are usually based in the community rather than in hospitals. The National Institute for Health and Care Excellence (NICE) recommends that the patient's social circumstances be assessed and their family involved as soon as possible.
Most areas of the UK have a community mental health care team which includes psychiatrists, nurses, psychologists, social workers, etc. A key worker such as a community psychiatric nurse or psychiatric social worker is usually allocated to co-ordinate the care for each person with schizophrenia.
Hospital treatment
Some people need to be admitted to hospital for a short time. This is sometimes done when the condition is first diagnosed so that treatment can be started quickly. Hospital admission may also be needed for a while at other times if symptoms become severe. A small number of people have such a severe illness that they remain in hospital long-term.
Electroconvulsive therapy (ECT) is not often used for the treatment of schizophrenia but may be considered when other treatments have not been effective.
People with schizophrenia often do not realise or accept that they are ill. Therefore, sometimes when persuasion fails, some people are admitted to hospital for treatment against their will, by use of the Mental Health Act. This means that doctors and social workers can force a person to go to hospital. This is only done when the person is thought to be a danger to themself or to others.
What is the outlook?
In most cases there are recurring episodes of symptoms (relapses). Most people in this group live relatively independently with varying amounts of support. The frequency and duration of each relapse can vary. Some people recover completely between relapses. Some people improve between relapses but never quite fully recover. Treatment often prevents relapses, or limits their number and severity.
In some cases, there is only one episode of symptoms that lasts a few weeks or so. This is followed by a complete recovery, or substantial improvement without any further relapses. It is difficult to give an exact figure as to how often this occurs. Perhaps 2 in 10 cases or fewer.
Up to 2 in 10 people with schizophrenia are not helped much by treatment and need long-term dependent care. For some, this is in secure accommodation.
Depression is a common complication of schizophrenia.
It is thought that up to a third of people with schizophrenia misuse alcohol and/or illegal drugs. Helping or treating such people can be difficult.
About 1 in 10 people with schizophrenia end their own life.
The outlook (prognosis) is thought to be better if:
Treatment is started soon after symptoms begin.
Symptoms develop quickly over several weeks rather than slowly over several months.
The main symptoms are positive symptoms rather than negative symptoms.
The condition develops in a relatively older person (adults with schizophrenia aged over 25).
Symptoms ease well with medication.
Treatment is taken as advised (that is, compliance with treatment is good).
There is good family and social support which reduces anxiety and stress.
Misuse of recreational drugs or of alcohol does not occur.
Newer medicines and better psychological treatments give hope that the outlook is improving.
Further reading and references
- Psychosis and schizophrenia in children and young people; NICE Clinical Guideline (January 2013, updated Nov 2022)
- Psychosis and schizophrenia in adults: prevention and management; NICE Clinical Guideline (Feb 2014 - last updated March 2014)
- Rehabilitation for adults with complex psychosis; NICE guidance (August 2020)
- Psychosis and schizophrenia; NICE CKS, September 2021 (UK access only)
- Useful contacts for support for schizophrenia; MIND.
- Guaiana G, Abbatecola M, Aali G, et al; Cognitive behavioural therapy (group) for schizophrenia. Cochrane Database Syst Rev. 2022 Jul 12;7(7):CD009608. doi: 10.1002/14651858.CD009608.pub2.
- Hasan A, von Keller R, Friemel CM, et al; Cannabis use and psychosis: a review of reviews. Eur Arch Psychiatry Clin Neurosci. 2020 Jun;270(4):403-412. doi: 10.1007/s00406-019-01068-z. Epub 2019 Sep 28.
Article history
The information on this page is written and peer reviewed by qualified clinicians.
Next review due: 8 Sept 2027
9 Sept 2024 | Latest version
Are you protected against flu?
See if you are eligible for a free NHS flu jab today.
Feeling unwell?
Assess your symptoms online for free