A delusion of grandeur is a false or unusual belief about one’s power, wealth, talents, and other traits. A person may believe, for instance, that they are famous, can end world wars, or that they are immortal.
Delusions of grandeur, also called grandiose delusions, often accompany other mental health symptoms, including other delusions. They may be related to mental or physical health conditions, including schizophrenia, bipolar disorder, or some types of dementia.
This article takes a more in-depth look at delusions of grandeur, including the different types, symptoms, causes, and possible treatments.
People experiencing delusions of grandeur see themselves as great, highly accomplished, more important than others, or even magical. The delusion may be persistent, or it may appear only periodically.
According to a 2025 review, grandiose delusions are 1 of 10 types that the Diagnostic and Statistical Manual of Psychiatric Disorders, 5th Edition (DSM-5) recognizes.
Some people with delusions of grandeur may also experience other types of delusions, such as a fear of persecution or unusual religious beliefs.
However, a delusion of grandeur is more than just very high self-esteem or an inflated sense of self-importance. It marks a significant disconnection from the real world. A person with delusions of grandeur may continue to believe in the delusion in spite of contradictory evidence.
Delusions of grandeur come in many forms. Many people experience delusions of a similar theme over time.
Delusions of grandeur can manifest in virtually limitless ways. Some potential types include:
- an inflated belief in one’s own importance, such as having the power to end war
- a belief that one is famous or occupies a high position in society
- a belief that one is a religious leader
- a belief in one’s ability to live forever
- a false belief that one cannot experience harm from disease or injury
- an inflated sense of intelligence
- a belief that one possesses magical skills, such as the ability to read minds
Some
Culture affects a person’s knowledge and beliefs about the world. Something that is considered a delusion in one culture might not be in another.
A person believing in their own greatness is the hallmark of a delusion of grandeur.
For the belief to be a delusion, it must be unreasonable and incorrect. For instance, a person who claims to be president of the United States, when they clearly are not, is an example of a delusion of grandeur.
There may be other symptoms along with an inflated false belief of one’s own importance. These include:
- difficulty getting along with others because of the delusion
- a persistent belief in the delusion despite contrary evidence
- dismissal of or anger at people who refuse to accept the delusional belief
- persistent attempts to get others to accept the belief
- behaving as if the belief is true
- experiencing other delusions
Because delusions of grandeur are usually related to a mental health condition, most people with this symptom also experience other mental health symptoms.
The prevalence of grandiose delusions may depend on other conditions a person has.
Delusions of grandeur are a type, or potential symptom, of psychosis. In a 2023 study of 798 people with psychosis, 375 (around 47%) had delusions of grandeur.
The following conditions may cause delusions of grandeur:
Bipolar disorder
Bipolar disorder is a condition characterized by periods of depression and periods of mania.
Research suggests delusions of grandeur are prominent in people with bipolar disorder, particularly those in a manic state.
A 2022 review suggests that the lifetime prevalence of grandiose delusions in people with bipolar disorder ranges from 24% to 69%.
Schizophrenia
Schizophrenia is a mental health condition characterized by delusions, hallucinations, and difficulty understanding reality.
This condition can cause unusual thought patterns, changes in mood or behavior, difficulty focusing, memory issues, and difficulties performing daily tasks. People with schizophrenia may have several delusions that affect their daily lives.
Some research suggests that around half of people with schizophrenia experience delusions of grandeur.
A similar disorder, schizoaffective disorder, may also cause delusions and hallucinations.
Narcissistic personality disorder
People with narcissistic personality disorder have a greatly inflated sense of their own importance. They seek validation and flattery, believe themselves to be special and unique, and lack empathy.
This condition causes a pattern of grandiosity. In
Dementia
Dementia progressively reduces a person’s ability to think clearly. It can affect the way they interact with the world, plan, and think.
As dementia progresses, some people develop delusions, including delusions of grandeur. People with dementia who have delusions of grandeur typically have many other symptoms, including significant memory issues.
Brain injury
Traumatic brain injuries can increase a person’s risk of developing psychosis symptoms, which can involve delusions.
Damage to the brain can sometimes change the way people think. Brain injuries may also cause hallucinations, memory problems, personality changes, and difficulties with basic skills, such as reading.
Many brain injuries are due to trauma, such as being hit in the head during a car accident. Brain lesions, strokes, and brain tumors can also damage the brain.
Treating delusions of grandeur can be challenging. These delusions may feel good to the person who experiences them. Moreover, because people with delusions truly believe in their delusions, they may not believe they need treatment.
The most suitable treatment for someone may depend on any underlying health conditions they have. For example, people with bipolar disorder
Individual and group therapy may also help people to develop healthier relationships with others. People with delusions related to personality disorders may need comprehensive, ongoing therapy to offset the effects that delusions have on their personality.
Delusions can be difficult to treat. Treatment often focuses on managing and reducing symptoms rather than curing the underlying condition. Depending on the cause, someone with delusions may need to take medication or have long-term therapy.
A person who experiences delusions is often unaware that their behavior is not usual, though it can be unsettling for other people to witness. Because delusions of grandeur make a person feel important, they may not want to give them up.
Helping a person see how their delusions negatively affect their life or relationships may help. With support and treatment, people with delusions can have happy relationships and lives.