Delusions: Types, Causes, & Related Disorders

What Are Delusions?

Delusions are false beliefs or ideas that aren’t based in reality but are held with strong conviction, even when presented with evidence they are untrue.^2,3,4 Having repeated delusions is a hallmark symptom of psychosis, which is an inability to accurately perceive reality.^1,2 Delusions can occur with or without other psychotic symptoms like hallucinations or disorganized thinking or speech.¹

What are Delusional Disorders?

When delusions persist for a month or more, it can be a sign that someone is suffering from delusional disorder, an uncommon type of psychotic disorder, with an estimated US prevalence of about 0.02%.^1,3,9 Delusional disorders are only diagnosed when delusions are the primary symptom a person experiences, and when the delusions cannot be attributed to another disorder.¹

In order to be diagnosed with this condition, a person’s delusions cannot be attributed to one or more of the following conditions:^1,3,4,5,6. It is much more common to have delusions as one of the symptoms in the following conditions than it is to have them as a sole issue.

• Major depressive disorder with psychotic features which usually involves delusions during severe depressive episodes
• Bipolar disorder with psychotic features or during manic episodes, where a person experiences increased energy, impulsivity, and euphoric mood
• Obsessive compulsive disorder, which causes intrusive, obsessive thoughts. Most people with OCD retain some awareness that their obsessions are not realistic, but the DSM-5-TR includes a specifier (‘with absent insight/delusional beliefs’) for people who become fully convinced their OCD beliefs are true.¹¹
• Personality disorders that cause abnormal mood, thoughts, behaviors, and interpersonal patterns (especially schizotypal, paranoid, schizoid, and narcissistic)
• Substance use disorders where delusions are often a result of the effects of using mind and mood altering drugs
• Brief psychotic disorder or delirium, which both involve a temporary state of confusion or psychosis, often in response to stress, change, or traumatic events
• Schizophrenia or schizoaffective disorder (which combines psychotic symptoms with major mood episodes, either depressive or bipolar type)¹²
• Neurological issues or conditions like Alzheimers, Parkinson’s disease, dementia or traumatic brain injuries

What Are the Main Categories of Delusions?

The DSM-5-TR, the diagnostic manual published by the American Psychiatric Association, recognizes 7 subtypes of delusional disorder: erotomanic, grandiose, jealous, persecutory, somatic, mixed, and unspecified.⁹ Clinicians also describe delusions along broader dimensions, such as bizarre vs. non-bizarre and mood congruent vs. mood incongruent. These groupings help identify the cause of the delusions, guide an accurate diagnosis, and help determine what is a delusion vs a strongly held belief, idea, or value.

These 4 descriptive dimensions of delusions are:^1,4

1. Bizarre delusions: Bizarre delusions are odd, strange, and unrealistic in nature.  Examples include believing in alien abductions, supernatural powers, or that a person has visited a parallel universe.
2. Non-bizarre delusions: Non-bizarre delusions are more realistic in nature, but still unlikely to occur. They can include beliefs about being followed, poisoned or stalked.
3. Mood congruent delusions: Mood congruent delusions occur during times when people experience strong emotions. Examples include experiencing paranoid delusions when having anxiety or grandiose delusions during a manic episode.
4. Mood-neutral delusions: Mood-neutral (also called mood-incongruent) delusions don’t only occur during times when a person is having strong emotions or under a lot of stress. These delusions can seem to come “out of nowhere” and may be a sign of a neurological, psychotic, or delusional disorder.

Under the older DSM-IV, delusional disorder could only be diagnosed when delusions were non-bizarre. Since DSM-5, bizarre delusions no longer rule out the diagnosis; clinicians instead note the specifier ‘with bizarre content.’¹⁰

What Are the 7 Types of Delusions?

Delusions can come in many forms, but there are some types of delusions that are more common than others. The most common delusions often have themes that either reflect strong emotions someone feels or beliefs or ideas they’ve been exposed to.^3,4 Below are some of the more common types of delusions that some people experience.

Grandiose Delusions

Delusions of grandeur, or grandiose delusions, center around an inflated sense of self.^1,3,4,7 People with grandiose delusions may believe they are superior to others or possess special abilities or talents. Some delusions of grandeur are extreme, and include religious delusions about being chosen by God or having supernatural abilities.⁴ During a manic episode, someone with bipolar disorder may become overconfident in their abilities and talents, leading to reckless acts.¹

Persecutory Delusions

Persecutory delusions are sometimes called paranoid delusions because they often involve beliefs of being hunted, followed, or targeted by someone or something.⁴ Examples of delusions that are persecutory include beliefs about someone trying to poison, kill, or cast evil spells on them. They may have surveillance delusions, and believe that a device or person is watching and tracking them. Paranoid and persecutory delusions can take many forms, but all involve a strong belief and fear of being attacked, targeted or threatened.⁷

Jealous Delusions

Jealous delusions usually involve a belief that a romantic or sexual partner is cheating or being unfaithful.^1,4,7 While jealous feelings are normal and something most people have experienced, jealous delusions are often recurring, intense, and very distressing. These types of delusions may occur in people without serious mental illnesses, but who instead struggle with insecurities, sexual dysfunctions, or codependence.⁴

Somatic Delusions

Somatic delusions often involve fears about a medical problem or underlying physical health issue.^1,4,7 For example, a person with OCD may develop intrusive thoughts and fears about having a specific disease, and spend hours researching symptoms and consulting with specialists. Other somatic delusions may involve beliefs about being infested with bugs or parasites, being pregnant, or something being wrong with a certain body part.^4,7

Erotomanic Delusions

Erotomanic delusions involve unfounded beliefs about infatuation and love. Usually, someone with erotomanic delusions believes that someone else is in love with them. This may be a person they are casually acquainted with, or it could be someone they’ve never met. A common erotomanic delusion is a person believing that a celebrity is secretly in love with them. These kinds of delusions can sometimes escalate into aggressive, jealous, or even illegal actions like stalking or harassment.^4,7

Religious Delusions

Religious delusions are false beliefs with spiritual content, such as being convinced that God, Satan, or another entity is speaking to you, controlling you, or has chosen you for a secret purpose.^1,4,7 They must be distinguished from sincerely held religious or cultural beliefs, which are not delusions. For example, there are some cultures that believe in witchcraft or voodoo, which are less common beliefs in Western cultures.

Guilty Delusions

Guilty delusions often stem from regrets or feelings of shame about a past mistake or action. One example is a person who is convinced they are going to hell or being punished because of certain bad deeds or ‘sins’. People with guilty delusions may struggle with depression, shame or low self-esteem, and may believe they’re bad or evil people who aren’t deserving of kindness. ⁴

Nihilistic Delusions

Nihilistic delusions involve beliefs that there is no meaning or point in life, or cynical beliefs about a person’s own existence. For example, a person with nihilistic delusions may be convinced that they do not really exist or that their life isn’t real. ^4,7 They may believe that their reality is artificially constructed, similar to what’s portrayed in the movies the Matrix or the Truman Show. The belief that you are already dead, do not exist, or have lost your organs or soul is known as Cotard’s syndrome, a rare condition first described by French neurologist Jules Cotard in 1880.^4,15

Other Types of Delusions

Mixed delusions involve more than one delusional theme at the same time, and some delusions do not fit any of the common categories listed above.¹

Some of the other types of delusions that may be experienced by people include:^1,3,7

• Bizarre delusions: Delusions involving strange or unrealistic ideas, like beliefs about parallel dimensions, extraterrestrial origins, or monsters. Other bizarre delusions may involve strong beliefs that certain extraordinary things happened to them in the past, like that they had a brain or alien microchip implanted as a child.
• Thought broadcasting: delusions that involve a belief that other people can hear their thoughts or read their minds. Thought broadcasting can also involve the belief that a person can communicate telepathically with others or that their thoughts can be broadcast through devices or machines.
• Thought insertion or thought withdrawal: delusions that involve the belief that other people, objects or entities are ‘inserting’ thoughts into their mind, as in a form of mind control. Thought withdrawal delusions involve the belief that thoughts are being or have been taken or extracted from the mind.
• Thought control: The belief that someone or something is exerting control over their thoughts or that their thoughts, feelings, and ideas are not their own. These delusions often involve the belief that the person has no ability to control their thoughts, feelings, or actions.
• Delusions of reference: Reference delusions involve irrational beliefs about a secret connection between unrelated events, objects, people, or situations. Finding hidden connections is a common theme in delusions of reference, and may involve believing that they are receiving coded or secret messages from TV or other media.

What Causes Delusions?

Most people who experience persistent delusions are suffering from an underlying physical or mental health issues or a neurological condition.^1,3,4 Delusions are more common in people with mood disorders, psychotic disorders, substance use and personality disorders. In some instances, delusions can occur in response to high levels of toxic stress, trauma, or sudden and distressing life changes. ^3,5,6

Genetic makeup and personality traits can make some people more prone to psychotic symptoms, including delusions.⁶ Also, people who experienced certain types of childhood trauma are more likely to develop psychiatric conditions known to cause delusional thinking.⁸ In many cases, delusions may even be an attempt to cope or make sense of these events.^3,4

Some experts theorize that delusions are a result of faulty logic or errors in thinking, like linking unrelated events together in an attempt to organize information or make sense of experiences.⁴ Cultural factors can also cause differences in the way people perceive reality. People who immigrate from other countries are more likely to report delusional thoughts, which may actually be a result of their culture, and not a sign of a mental illness.³

How Do You Help Someone With Delusions?

The most effective way to help someone with delusions is to express concern calmly, avoid arguing about the belief, and encourage professional help. Confronting or trying to disprove the delusion usually agitates the person and can deepen their distrust. In some cases, these kinds of confrontational approaches (even from loved ones) can further isolate the person, worsen their delusions, and cause them to experience more severe psychotic symptoms.⁷

Expressing concern for them is usually the best way to initiate a conversation with them about their mental health. Use a non-judgemental approach and try to avoid debating or challenging their delusional ideas.⁷ If possible, encourage them to seek out counseling or talk to a mental health professional, but try not to do this in a way that seems like you’re calling them crazy. For example, express concern about their stress levels or mention that therapy has really helped you.

If you have reason to believe they’re unsafe (a danger to themselves or others), it may be necessary to involve the officials or initiate an involuntary commitment order (IVC order). Always use this as a last resort, and remember that seeking treatment on a voluntary basis is the most ideal outcome. The process for initiating an involuntary commitment varies by state; it may go through a magistrate, a county court, or a local crisis services agency, so check your state’s process or ask NAMI’s helpline where to start.¹⁴ In a mental health crisis, you can call or text 988 to reach the 988 Suicide & Crisis Lifeline, which launched nationwide in July 2022.¹³ If there is immediate physical danger, call 911 and request a CIT-trained officer, a police officer who has received special training in handling mental health crises.

How Are Delusions Treated?

Someone experiencing delusions is usually in need of immediate mental health treatment. If the delusions are leading to dangerous or harmful behaviors (like suicidal, homicidal, or aggressive behavior), some may even require inpatient treatment. Many people with persistent delusions are suffering from a serious underlying mental health issues, which may require long term therapy as well as psychiatric medication, most often antipsychotic medication.⁵

Because there are so many different kinds of mental health conditions that can cause delusions, it’s important for a person to receive a full diagnostic evaluation. The type of treatment needed depends on the underlying cause or condition causing the delusions. In many instances, a combination of medication and therapy is effective at managing symptoms of psychosis. In some cases, treatment can even help someone experiencing delusions make a full recovery.³

Most people begin this process by finding a therapist, using an online therapist directory, or visiting a local mental health inpatient or outpatient clinic. It’s important to find the right therapist who is experienced in treating delusions and if needed, has crisis support at their agency (like a 24 hour crisis line, on-site psychiatrist, or more intensive levels of care).

Can People Recover From Delusions With Therapy?

Yes. Research from the University of Oxford shows that targeted psychological therapy can lead to recovery from even persistent delusions. In the largest trial of its kind, published in The Lancet Psychiatry in 2021, patients with long-standing persecutory delusions who completed 6 months of a modular cognitive therapy called the Feeling Safe Programme showed the largest treatment effects ever reported for persistent delusions (Cohen’s d of 0.86 for delusional conviction versus an active control).¹⁶

The Feeling Safe Programme was developed by NIHR Research Professor Daniel Freeman and colleagues at Oxford over more than a decade. Rather than debating the delusion itself, it works on the factors that keep the fear going: poor sleep, excessive worry, low self-confidence, and safety behaviors like avoiding public places. Patients then re-enter feared situations to relearn, through direct experience, that they are safe. In the 2021 randomized controlled trial of 130 NHS patients, Feeling Safe outperformed befriending sessions delivered by the same therapists.¹⁶

The approach is now being adapted for wider access. In June 2025, Freeman’s team published results for Feeling Safer, a 6-month therapist-supported online version, in Psychological Medicine. In the initial cohort, patients showed very large reductions in persecutory delusions, and the program advanced to a full randomized trial.¹⁷ For someone experiencing delusions, the practical takeaway is that specialized talk therapy, alongside medication when needed, is an evidence-based route to recovery, not just symptom management.

Final Thoughts

Delusions are false, irrational, but strongly held ideas or beliefs.^1,2,3,4 Delusions are sometimes caused by high levels of stress, anxiety, or traumatic experiences, but are often a sign of a more serious mental illness.¹ If you or someone you care about is experiencing delusions, it’s a good idea to seek treatment right away, which may involve a combination of inpatient or outpatient therapy and medication.⁵