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About psychotic disorders

Psychosis usually develops between the ages of 15 and 25. It happens in serious mental illnesses such as schizophrenia, severe depression, or bipolar disorder. Conditions that cause psychosis are called psychotic disorders.

Psychosis can also happen as a result of severe stress or drug or alcohol use, and then might never happen again. One in five people who have psychosis for the first time get better and never have it again.

Causes of psychosis


Schizophrenia is a chronic (long-lasting) condition that affects about 1% of people. It usually shows for the first time when people are younger than 30.

People with schizophrenia may experience hallucinations (seeing, hearing, feeling, or smelling something that's not there) and delusions (beliefs that don't match reality). They may be unable to think clearly, withdraw socially, and stop taking care of themselves (self-neglect).

There is no cure for schizophrenia. Treatment is with medicines, education, and talking therapy. It aims to prevent psychotic episodes.

Schizophrenia affects people from all groups in society. You can find out more about schizophrenia on this page.

Bipolar disorder

Bipolar disorder is a long-lasting mental health condition that runs strongly in families.

When a person develops bipolar disorder, psychotic symptoms can be the first sign that something is wrong. They may also be depressed or have what's called an elevated mood or mania (this means they are unusually happy or irritable, hyperactive, don't need normal amounts of sleep, and are flooded with ideas and speak rapidly). As well, they may lose touch with reality and have unusual ideas or behaviours.

The symptoms of bipolar disorder often aren't constant – they can come and go. It's treated with medications, education, and talking therapy, which usually work well. You can read more about bipolar disorder on these pages.

Severe depression

Severe depression, including severe postnatal depression, can also trigger psychosis. It may happen just once, or it may go away then come back when the person is very depressed again. You can read more about depression in this section, and this page, which has links to more information about postnatal depression.

On the next page: Do I have a psychotic disorder?

Written by HealthInfo clinical advisers. Endorsed by consultant psychiatrist, Canterbury DHB. Last reviewed April 2016.

See also:

Bipolar disorder


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Page reference: 826484

Review key: HIPSY-124133