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Schizophrenia is a mental health problem. 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.

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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.

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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.

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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 activities 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.

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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.

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.

  • Illegal or street 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 amfetamines, 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.

How is the diagnosis made?

Some of the symptoms that occur in schizophrenia also occur in other mental health conditions such as depression, mania, and dissociative identity disorder, or after taking some street drugs. Therefore, the diagnosis may not be clear at first. As a rule, the symptoms need to be present for several weeks before a doctor will make a firm diagnosis of schizophrenia.

Not all symptoms are present in all cases. Different forms of schizophrenia occur depending upon the main symptoms that develop. For example, people with paranoid schizophrenia mainly have positive symptoms which include delusions that people are trying to harm them. In contrast, some people mainly have negative symptoms and this is classed as simple schizophrenia. In many cases there is a mix of positive and negative symptoms.

Sometimes symptoms 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.

Schizophrenia treatment

Treating schizophrenia usually involves a combination of medication, therapy and self-management techniques. These 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 and physical problems and is being increasingly used as a treatment for 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:

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.

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 (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 illegal drugs or of alcohol does not occur.

Newer medicines and better psychological treatments give hope that the outlook is improving.

Further reading and references

Article history

The information on this page is written and peer reviewed by qualified clinicians.

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