What Is Delusional Disorder?

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What Is Delusional Disorder?

Delusional Disorder

Delusional disorder is a psychotic disorder that can make it hard for a person to distinguish between what’s real and what’s imaginary. The primary symptom of this condition is the presence of delusions, which are irrational, unshakeable beliefs that are untrue.

People with delusional disorder may experience bizarre or non-bizarre delusions:

  • Bizarre delusions: These are delusions that are physically impossible in our reality. For instance, the person may believe that an organ has been removed from their body without there being any evidence of the procedure.
  • Non-bizarre delusions: These are delusions that could possibly occur in real life, although they are often highly exaggerated misinterpretations of situations. For instance, the person may believe that their neighbor is plotting to kill them or that someone walking behind them on the pavement is actually following them.

This article explores the types, symptoms, causes, diagnosis, and treatment of delusional disorder.

Types of Delusional Disorder

Delusional disorder is classified into different types, depending on the type of delusions the person experiences:

  • Persecutory delusional disorder: Persecutory delusions, also known as paranoid delusions, can cause the person to believe that someone is trying to follow, spy on, mistreat, or harm them in some way. As a result, they may make repeated complaints to the authorities for help. 
  • Grandiose delusional disorder: The person may have an exaggerated sense of their own self-worth, talents, knowledge, status, or identity. For instance, they may believe they are exceptionally talented or that they have made an important discovery.
  • Jealous delusional disorder: The person may believe that their partner or spouse is cheating on them, even though that is not the case and there is no evidence to support this belief.
  • Erotomanic delusional disorder: The person may believe that someone—often someone famous or important—is in love with them. They may try to contact the person or stalk them, and get into trouble with the authorities as a result.
  • Somatic delusional disorder: Somatic delusions are related to the person’s body, health, or appearance. The person may believe they have a health condition, a strange appearance, a parasite in their body, or a foul odor emanating from their mouth.
  • Mixed delusional disorder: The person experiences two or more different types of delusions.

Symptoms of Delusional Disorder

These are some of the symptoms of delusional disorder:

  • Lack of awareness that the delusions are imaginary
  • Inability to accept that the delusions are untrue
  • Defensiveness in response to criticism
  • Preoccupation with hidden motives of friends and family members
  • Fear of being tricked, mistreated, or taken advantage of
  • Intense, irrational suspicion and mistrust
  • Feelings of guilt, fear, anger, or betrayal
  • Paranoia and hypervigilance against perceived threats
  • Inability to relax
  • Argumentative nature
  • Tendency to hold grudges
  • Difficulty forgiving perceived slights
  • Bizarre, aggressive, or violent behavior in response to delusions

It’s important to understand that the delusions are very real to the person experiencing them.

Causes of Delusional Disorder

While the exact causes of delusional disorder are unknown, these are some of the risk factors that can contribute to the development of the condition:

  • Genetic factors: Delusional disorder may be genetic, so people may be more likely to have this condition if a biological relative has delusional disorder or schizophrenia.
  • Biological factors: Abnormalities in certain parts of the brain and imbalances in brain chemicals known as neurotransmitters can cause delusional symptoms.
  • Environmental factors: Factors such as stress, social isolation, alcohol use disorder, and substance use disorder can make a person more likely to experience delusions.
  • Psychological factors: Personality traits such as hypersensitivity, suspicion, distrust, envy, and low-self esteem can cause a person to seek explanations for these feelings, causing them to form delusions as a result.

Diagnosing Delusional Disorder

Healthcare providers diagnose delusional disorder by determining whether the person’s symptoms meet the diagnostic criteria listed in the Diagnostic and Statistical Manual of Mental Disorders (DSM-V), a guiding manual published by the American Psychiatric Association.

The diagnostic criteria for delusional disorder listed in the DSM-V are as follows:

  • The person has experienced one or more delusions
  • The delusions have persisted for at least one month
  • The person hasn’t experienced hallucinations or other affective symptoms

The diagnostic process may involve a complete medical history, a physical examination, a long interview, and specially designed questionnaires, in addition to other tests or scans to help rule out other health conditions.

It’s important to note that delusions can occur as a symptom in several mental health conditions, such as schizophrenia, bipolar disorder, fronto-temporal dementia, Alzheimer’s disease, and Parkinson’s disease, among others.

However, these conditions tend to be accompanied by several other symptoms in addition to delusions, such as hallucinations, disorganized thinking, and abnormal motor behavior, for instance.

When it comes to delusional disorder, on the other hand, delusions are the most prominent symptom. Therefore, the diagnostic criteria distinguishes between delusional disorder and other conditions by noting the lack of other psychotic or affective symptoms.

Treating Delusional Disorder

People with delusional disorder may be unlikely to seek treatment because they may not realize that their delusional beliefs are not true.

This condition can be difficult to treat, because the person’s suspicious nature and delusional beliefs can cause them to believe their loved ones and healthcare providers are trying to harm them. However, recovery is possible, especially if the healthcare provider is able to earn the person’s trust.

Treatment for delusional disorder typically involves:

  • Antipsychotic medication: Antipsychotic medications work by improving the balance of neurotransmitters in the brain, thereby reducing delusions. They can also help reduce the agitation and inappropriate behaviors the person may experience.
  • Cognitive behavioral therapy (CBT): CBT can help people challenge the delusions they are experiencing and work toward reality. Once the therapist has gained the person’s trust, they can also help the person improve their social skills and improve their self-confidence.

A Word From Verywell

If you or a loved one are experiencing delusions, it can be helpful to visit a mental healthcare provider such as a psychologist or psychiatrist as soon as possible. Your primary care doctor can provide a reference, if you need one.

9 Sources
Verywell Mind uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
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By Sanjana Gupta
Sanjana is a health writer and editor. Her work spans various health-related topics, including mental health, fitness, nutrition, and wellness.