Schizophrenia is a mental illness that affects one in 100 people.
In general, it starts in late teens or early 20s.
Schizophrenia can come and go. After an initial attack about one third of people recover completely. A further third have occasional episodes, and the remaining third continue to have symptoms.
The illness can largely be controlled by medication.
People who have schizophrenia may experience either 'positive' or 'negative' symptoms.
Positive symptoms include strange behaviours, mood changes and delusions, such as the feeling of being watched. Some people have hallucinations, hear voices and lose touch with reality.
Negative symptoms include withdrawal from social contact, anti-social behaviour, feeling emotionally numb and lacking motivation. Sufferers may sleep during the day and wake at night and not take care of themselves.
The exact causes of schizophrenia are not known.
It tends to run in families and is linked with brain chemistry and brain damage at or before birth.
Stress and the use of illegal drugs such as acid and amphetamines may trigger schizophrenia.
Schizophrenia should be treated as soon as a diagnosis has been made so that patterns of thought don’t become fixed in the mind.
Anti-psychotic drugs stop some symptoms such as hearing voices and delusions although have little effect on symptoms such as lack of motivation.
The drugs can have unpleasant side-effects. Some people suffer facial grimaces, uncontrollable muscle movements, weight gain and extreme thirst.
For advice and information, go to the Rethink (formerly The National schizophrenia fellowship) website.