Hallucinations and delusions | Dementia Australia

Delusions are false ideas or beliefs that someone holds onto, even when there is evidence that they are not real. These beliefs are not shared by other people from the same:
For example, someone might believe they are the captain of the Australian rugby team, or that an alien has taken over the body of someone in their family.
No facts or reasoning can shake this belief. The delusion seems entirely real, and you (or they) may become completely preoccupied with it.
People with psychosis may have delusions and hallucinations (usually, hearing something that doesn't exist). They may also have other symptoms, such as confusion or memory problems.
Delusions can be confusing and scary.
There are several different types of delusions.
Delusions can be a symptom of some mental illnesses, such as:
Sometimes symptoms of psychosis (including delusions) can happen with conditions such as:
Substance use can also cause delusions. This can include:
Other causes of psychosis can include:
Your doctor will ask about your symptoms and how long you have had them. They will ask about medicines and other substances you have taken. They may also examine you to check your physical health.
Your doctor may recommend some tests to help with diagnosis. These may include:
See your doctor as soon as possible if you or someone you care for may be having delusions.
Your doctor may refer you to a mental health professional to help diagnose the cause of the delusions. This may be a psychiatrist (doctor who specialises in mental health conditions).
A crisis assessment and treatment team (CATT) can respond to urgent requests to help people in mental health crisis 24 hours a day, 7 days a week.
Treatment will depend on the cause of your delusions.
Medicines can be used to treat delusions, including:
Depending on the cause of the delusions, other therapies are also sometimes used. These may include:
Your doctor, psychologist or psychiatrist may be able to help with these treatments.
Community support programs are also available and may be suitable for some people with delusions. These can help with:
Ask your doctor, social worker or specialist about support programs.
If someone you know is having delusions, remember that the delusions may seem very real to that person. You can help by:
It's best not to:
Make sure you also get support for yourself if you are caring for someone with psychosis.
The following resources can help if you are concerned about delusions.
You can also call the healthdirect helpline on 1800 022 222 (known as NURSE-ON-CALL in Victoria). A registered nurse is available to speak with 24 hours a day, 7 days a week.
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Last reviewed: April 2024



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