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Causes of paranoia

3-minute read

Paranoia is not always due to a mental illness. Recent studies have shown that mild paranoid thoughts are fairly common in the general population. Mental disorders that cause paranoia include:

Paranoid personality disorder

A personality disorder is a long standing pattern of problematic thoughts, feelings and behaviour. People with paranoid personality disorder have a tendency to assume that others will harm, deceive or take advantage of them. They may appear secretive, argumentative or cold and be difficult to get along with. This disorder is uncommon and usually improves with age so that many people recover by their 40s or 50s.

Delusional disorder

People with a delusional disorder have one delusion (a fixed, false belief) without any other symptoms of mental illness. Paranoid delusions are the most common, but people with a delusional disorder can also have other types of unusual beliefs.

Paranoid schizophrenia

Schizophrenia is a form of psychosis and causes people to have trouble interpreting reality. The main symptoms are hallucinations (such as hearing voices that aren’t there) and delusions (fixed, false beliefs). Some people with schizophrenia have bizarre delusions such as believing that their thoughts are being broadcast over the radio or they are being persecuted by the government. Other symptoms include confused thinking and reduced motivation for everyday tasks.

Other causes of paranoia include:

Where to get help

If you need help, talking to your doctor is a good place to start. If you’d like to find out more or talk to someone else, here are some organisations that can help:

  • SANE Australia (people living with a mental illness) – call 1800 18 7263.
  • beyondblue (anyone feeling depressed or anxious) – call 1300 22 4636 or chat online.
  • Black Dog Institute (people affected by mood disorders) – online help.
  • Lifeline (anyone having a personal crisis) – call 13 11 14 or chat online.
  • Suicide Call Back Service (anyone thinking about suicide) – call 1300 659 467.

Last reviewed: December 2016

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