Schizophrenia is a chronic mental health condition, sadly surrounded by misunderstanding and stigma. Yet it is the most common psychotic illness, affecting around twenty million individuals worldwide.

In a nutshell, it is a disorder characterised by hallucinations and delusions. Auditory hallucinations include voices either heard in the first person, i.e. telling the individual to perform an act, or in the third person, for example a running commentary such as 'he is going for a walk'. Delusions may be those of grandeur, such as 'I am the Son of God', or persecution - 'everyone hates me'.

By essence, hallucinations and delusions are only experienced by the person affected.

Disordered thought includes concerns that ideas are being inserted into your head by an external force, or others being able to hear your thought processes - 'thought broadcasting'. Persons with untreated schizophrenia may lose interest in their person and surroundings, so that self-neglect and apathy become issues.

Typically, a diagnosis is made between the ages of 15-35, but subtle symptoms may be present for up to 10 years before formal recognition. Both sexes are affected equally. Risk factors are both genetic and environmental. You are more likely to be affected if you have a first degree relative with the condition.

Schizophrenia is associated with infection while in the uterus, low birth weight and neurodevelopmental issues in early life. Though contested by some, there is a definite link between recreational drug use and the development of symptoms, which may commence several years after substance misuse has finished. A link with negative or abusive parenting has been demonstrated, and schizophrenia is higher in migrants and those displaced.

Diagnosis firstly aims to rule out organic causes for symptoms. These are wide ranging and include disorders in blood chemistry; poisoning, including alcohol poisoning; and disorders of the brain, such as dementia, epilepsy and even a tumour. Due to the complexity of the condition, specialists in psychiatry are likely to be involved from early on.

Diagnosis and treatment are important: it is a treatable condition, which if addressed can yield significant benefit. However according to the World Health Organisation, more than two thirds of those with schizophrenia are not receiving the appropriate care. As a result, these individuals are two to three times more likely to die than those of the same age without the condition. Many deaths are due to treatable causes, such as diabetes and heart disease. Untreated, the outcomes are bleak, with a suicide rate ten times greater than the background population.

Once a diagnosis is made, treatment consists of medication and talking therapies. Antipsychotic drugs are first line. Although the previous generation of preparations had significant side effects, newer medications are much more tolerable. The most common side effect is appetite stimulation and weight gain/ obesity. Cognitive Behavioural Therapy is an established treatment, and Family Therapy has been shown to be useful. Art therapy may improve symptoms in young people.

Even in low to middle income countries, excellent results can be achieved through a combination of easy access to medication and care in the community, including the recruitment of family support, while trying to help the individual to live as independently as possible.

As mentioned previously stigma and discrimination are rife. The condition is not that of 'split personality', rather during illness those affected are separated from reality. Schizophrenia does not automatically predispose the person to violence. The condition is not linked with reduced intelligence. Several highflyers in business and entertainment have been diagnosed with schizophrenia.

Though medication may often be required long term, up to 80 per cent will demonstrate improvement within the first year and 20 per cent will not have another psychotic episode within five years.

Remaining well relies on timely diagnosis, appropriate treatment and support, as well as rapid recognition of signs of potential relapse into illness.

Useful websites: