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Topic » Delusional Disorder

Delusional Disorder

Delusional Disorder

Delusional disorder is characterized by illogical or intense beliefs or suspicions that a person believes to be true. These beliefs may appear strange and bizarre. To diagnose someone with delusional disorder, the symptoms must last at least a month.

What Is Delusional Disorder?

Delusional disorder is a psychotic disorder in which the patient is unable to distinguish between what is real and what is imagined. A delusion is an incorrect or false belief that occurs as a result of a faulty interpretation of reality. Delusions, like all other psychotic symptoms, can occur as a result of a variety of complicated psychiatric disorders. When delusions are the most noticeable symptom, the term ‘delusional disorder’ is used.

In this case, a person holds a false belief strongly, notwithstanding the clear evidence or proof to the contrary. According to American Psychiatric Association, this disorder includes “a person having false beliefs (delusions) that persist for at least one month. The delusions can be bizarre (about things that cannot possibly occur) or non-bizarre (things that are possible but not likely, such as a belief about being followed or poisoned).”

As per the Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition (DSM-5), delusional disorder is an illness identified by at least 1 month of delusions devoid of any other psychotic symptoms. People with this condition, on the other hand, can continue to socialize and function normally without exhibiting any unusual or bizarre behavior. People with this condition are not like people with other psychotic disorders. However, there are situations or cases where a patient might get extremely preoccupied, leading to a disrupted lifestyle. Such a disorder commonly happens in middle to late life and is more prevalent in women than in men.

Read More About DSM 5 Here

Understanding Delusional Disorder

Constant delusions are the primary symptom of this psychotic disorder. These are defined as unshakable beliefs in things or elements that aren’t true. However, that does not mean that they’re completely unrealistic. It can include delusions that could happen in real life, such as being followed, deceived, poisoned, conspired against, or loved from a distance. On the other hand, bizarre delusion is something that can never happen in real life, such as cloning by aliens or having your views broadcast on TV. A person with such thoughts is considered delusional with bizarre-type delusions.

A study conducted by Theo C. Manschreck, M.D., M.P.H., states that delusional disorder is the current designation for a group of disorders with unknown causes and the primary feature being a delusion. Even though the specific content of the delusion may vary from one victim to another, it is the existence of the delusion, its longevity, its impact on behavior, and its diagnosis that unifies these seemingly different disorders. In considerable agreement with Emil Kraepelin’s concept of paranoia 1, the revised third edition of DSM-III-R provides sound criteria for distinguishing such cases and collecting systematic information about these conditions.

Types Of Delusional Disorder

Types of Delusional Disorder
Delusional Disorder


The different types of this condition are defined by the main theme of delusion. As per the study conducted by Theo C. Manschreck, here are some of the common types of delusions:

1. Bizarre

A type of delusion defined by a phenomenon that is considered totally implausible in reality.

2. Delusional Jealousy

A delusion that involves content catering to one’s sexual partner being unfaithful.

3. Erotomania

A delusion where the subject imagines another person with higher status is in love with him/her. It is a “Delusion of a special, loving relationship with another person, usually someone famous or of higher standing,” explains Harvard Health Publishing.

4. Grandiose

A delusion is defined by heightened value, knowledge, power, identity, or special relationship to a supreme being or famous person.

5. Of Being Controlled

A delusion that compels the subject to think that his/her feelings, impulses, thoughts, or actions are under the control of some external force rather than being under one’s own control.

6. Of Reference

A delusion that involves a theme catering to a particular event, object, or person in the subject’s immediate environment having a particular and unusual significance. Such delusions are usually negative or derogatory in nature, but also may be grand in content. This differs from the idea of reference, where the false belief is neither firmly held nor fully considered to be true.

7. Persecutory

Harvard Health explains that it is a “Delusion that the person is being threatened or maltreated.” Such a delusion involves situations whereby the victim or someone close to the victim is being attacked, harassed, cheated, persecuted, or conspired against.

8. Somatic

It is primarily a delusion caused by a physical illness or a physical defect. A delusion in which the main focus is on the appearance or operation of one’s body.

9. Thought Broadcasting

A delusion in which the patient or victim believes that his or her thoughts are being broadcast out loud in order for others to notice him or her.

10. Thought Insertion

The delusion in which the victim believes his or her thoughts are not his or her own but have been inserted by an external force.

11. Mood-Congruent Psychotic Features

Here, the delusions or hallucinations involve consistent content with typical themes of a depressed or manic mood. If the mood is depressed, the matter of the delusion involves themes catering to personal inadequacy, guilt, disease, death, nihilism, or deserved punishment. If the mood is manic, the content of the delusions is defined by themes of inflated worth, power, knowledge, or identity, or a special relationship to a deity or a famous person.

12. Mood-Incongruent Psychotic Features

In this case, the content of delusions is not consistent with the typical themes of a depressed or manic mood. In the case of depression, the delusions are defined by the idea of personal inadequacy, guilt, death, disease, nihilism, or deserved punishment. In the case of mania, the delusion is not defined by themes, such as inflated worth, knowledge, power or identity, or a special connection to a deity or a famous person.

Read More About Major Depressive Disorder (Depression) Here

Symptoms Of Delusional Disorder

Symptoms of Delusional Disorder
Delusional Disorder


This condition may amplify from an already paranoid personality disorder. Paranoid personality begins during early adulthood where the subject suffers from pervasive distrust and suspiciousness of others and their motives.

Early symptoms of the delusional disorder may include:

  • Feeling abused and exploited
  • Comprehending threatening meanings into harmless remarks or events
  • Doubting the loyalty or trustworthiness of friends
  • Having grudges for a prolonged period of time
  • Answering readily to perceived slights

However, the sufferer’s behavior may not be bizarre or odd. People with this disorder tend to function normally until their delusions cause problems. For example, a person may have a marital problem he/she is doubting his/her spouse to be unfaithful.

Other symptoms include:

  1. Non-bizarre delusions: Incidents that can happen in real life like being poisoned, followed, deceived, etc. However, in reality, it is not happening and only develops due to mistaken perceptions or experiences.
  2. Irritable, angry, or low mood: When a person is feeling annoyed, angry or sad or even threatened as he/she is holding on to a false belief.
  3. Hallucinations: Seeing, hearing, or feeling things that are absent in reality.

Factors Concerning Delusional Disorder

Factors Concerning delusional disorder
Delusional Disorder


According to a 2009 study2, there are a few factors that foster the development of delusions, such as:

  • Dysfunction in the working of the brain
  • Past incidents influencing of temperament and personality
  • Maintenance of self-esteem
  • The impact of a phenomenon
  • Facing perceptual disturbance
  • Depersonalization
  • Cognitive overload

Apart from these, the following factors may cater to the continuation of the disorder:

  • The inactivity of changing ideas and the lack of flexibility
  • The lack of interpersonal communication
  • Destructive behavior resulting from persecutory hallucinations leading to hostility
  • Delusions destroy respect and proficiency of the sufferer, thereby promoting compensatory delusional interpretation.

It has also been observed that these factors are perfect, however, some or all may act synergistically to initiate and maintain the delusion.

Stages Of Delusion Formation

Stages Of Delusion Formation
Delusional Disorder


Research reveals the following five stages involved in the formation of delusions:

  1. Trema- Delusional mood expressing a total change in the opinion about the world
  2. Apophany- Searching and finding a new meaning for psychological events
  3. Anastrophy- Heightening of the psychosis
  4. Consolidation- Building a new world or psychological set based on a new meaning
  5. Residuum- Eventual autistic state

Causes And Risk Factors For Delusional Disorder

The actual cause of the delusional disorder, like any other psychotic disorder, is unknown to professionals. However, researchers are examining the role of genetic, biological, environmental, or psychological factors that make it prevalent.

1. Genetic Factors

It’s possible that genes have a role in delusional illness because it’s more common in those who have a family member with a mental health problem or schizophrenia. It is thought that, like other mental disorders, a person’s chances of inheriting delusional disorder from his or her parents are high since it runs in the family.

Read More About Schizophrenia Here

2. Biological Factors

Researchers or experts in this field are still studying the abnormalities predominating certain areas of the brain as it might foster the development of delusional disorders. The key reason for this theory is defined by an imbalance of certain chemicals in the brain, called neurotransmitters. These chemicals are associated with the formation of delusional symptoms. An imbalance in these chemicals can conflict with the transmission of messages, leading to symptoms.

A 2010 study 3 suggests that “delusions result from aberrations in how brain circuits specify hierarchical predictions, and how they compute and respond to prediction errors.” The researchers found that certain defects in basic brain mechanisms can impair memory, perception, social learning, and bodily agency in a way that the sufferer may “experience an internal and external world that healthy individuals would find difficult to comprehend.”

3. Environmental And Psychological Factors

Incidents suggest that stress can also give rise to delusional disorder. Alcohol and drug abuse also contribute to the same. Additionally, people who tend to stay alone, remain socially withdrawn or those with poor vision and hearing capability, are more likely to have a delusional disorder.

Read More About Drug Abuse Here

Diagnosis Of Delusional Disorder

This psychotic disorder is diagnosed based on the following criteria:

  • The patient is suffering from one or more delusions that last for a month or more
  • The patient has never been examined with schizophrenia
  • Apart from suffering from delusions and the related effects, their life is not much affected, backed by normal behavior
  • Brief maniac or significant depressive episodes when compared with the delusions
  • If there is no such other mental disease, medication, or medical condition to hold responsible for

If the doctor comes across the symptoms of delusional disorder, then they will provide you with a complete medical record and conduct a physical examination. Although no particular laboratory tests exist to identify delusional disorder, the doctor may utilize diagnostic testing such as imaging examinations or blood tests to rule out physical illness as the cause of the symptoms. These are some of them:

  • Alzheimer’s disease
  • Obsessive-compulsive disorder
  • Epilepsy
  • Delirium
  • Other schizophrenia spectrum disorders 4

However, after examinations, if the doctor is left with no trail of physical issues leading to the symptoms, they might refer the patient to a psychiatrist or a psychologist, or a therapist trained to diagnose and treat such mental illnesses. They’ll interview the patient and use assessment tools to assess the person for a psychotic disorder. But “It is more difficult to make a diagnosis when the person with the disorder conceals his or her thoughts.” Because the individual is convinced of the truth of his or her ideas, he or she may refuse treatment.” adds Harvard Health.

Read More About Obsessive-Compulsive Disorder (OCD) Here

Treatment Of Delusional Disorder

Treatment catering to delusional disorder mostly includes medication and psychotherapy. Treating this type of mental condition can be difficult because the subject may be unaware of his or her condition or the psychiatric problem. Here are the various ways of treating delusional disorder.

1. Medication

The fundamental medication used to treat the delusional disorder in a person is called antipsychotics. Drugs in this type of treatment include:

A. Conventional Antipsychotics

Also known as neuroleptics, these drugs have been popular among doctors to treat mental illness since the mid-1950s. They work by blocking the dopamine receptors in the brain as it is a neurotransmitter and is considered to foster the development of delusions. Conventional antipsychotics include –

  • Chlorpromazine (Thorazine)
  • Thioridazine (Mellaril)
  • Thiothixene (Navane)
  • Loxapine (Oxilapine)
  • Haloperidol (Haldol)
  • Perphenazine (Trilafon)
  • Fluphenazine (Prolixin)
  • Trifluoperazine (Stelazine)

B. Atypical Antipsychotics

The introduction of newer drugs appears to be helpful in the treatment of the symptoms 5 of the delusional disorder with fewer side effects. They block both the dopamine and serotonin receptors in the brain. Serotonin is another neurotransmitter that is thought to promote the development of delusional disorder. These drugs include:

  • Aripiprazole (Abilify)
  • Asenapine (Saphris)
  • Aripiprazole Lauroxil (Aristada)
  • Brexpiprazole (Rexulti)
  • Clozapine (Clozaril)
  • Cariprazine (Vraylar)
  • Iloperidone (Fanapt)
  • Paliperidone (Invega Sustenna)
  • Lurasidone (Latuda)
  • Paliperidone Palmitate (Invega Trinza)
  • Ziprasidone (Geodon)
  • Quetiapine (Seroquel), Risperidone (Risperdal), Olanzapine (Zyprexa)

C. Other Medications

Sedatives and antidepressants also help in treating anxiety related to the disease. Tranquilizers are also used to calm down a patient with a high level of anxiety or sleeping issues. Antidepressants are used to treat depression, which is common in people with delusional disorder.

2. Psychotherapy

Additionally, indulging in psychotherapy can also be helpful along with medications. It is a better way to help individuals manage and cope with the health issues related to their false beliefs. The types of psychotherapies helpful in treating delusional disorder are:

A. Individual Psychotherapy

The treatment helps the subject to understand and improve the power of thinking that has become distorted.

B. Cognitive-Behavioural Therapy (CBT)

CBT 6 can enable the subject to learn, identify and change thinking patterns along with behaviors that lead to disturbing feelings. According to a 2009 study, CBT 7 can help to significantly improve negative symptoms of paranoid schizophrenia and reduce paranoid delusions after 6 months of treatment.

Read More About Cognitive-behavioral Therapy Here

C. Family Therapy

It can help families take care of the loved one who is suffering from delusional disorder by helping the person. Family therapy can be substantially helpful in the management of mental health conditions that lead to delusions like schizophrenia and delusional disorder.

Complications Related With Delusional Disorder

Delusional disorder is associated with various complications mentioned below.

  • Individuals with delusional disorder may suffer from depression due to the difficulties connected with the delusions.
  • During the period of delusional disorder treatment, complications such as violence or legal problems may take place.
  • People with the delusional disorder tend to become separated from others, especially if the illness intervenes or adds tension to their relationships.

Prevention Of Delusional Disorder

Even today, there are no known ways to prevent delusional disorder. However, with early diagnosis and on-time treatment, the disorder can lessen the disturbances to the person’s life, family, and friendships.

Prognosis For Delusional Disorder

The delusional disorder differs, based on the person, the type of disorder, and the severity of the symptoms. Moreover, life events experienced by the patient should also be considered backed by the presence of support and the enthusiasm to cooperate with the treatment. The condition is typically an ongoing illness, however, with the right treatment, people can heal from the symptoms. While some recover completely, others may have sessions of delusional beliefs.

However, people with this disorder do not want to seek help. Subjects find it difficult to accept that they have a mental illness. Additionally, they hold their surrounding environment responsible for the symptoms. Many feel embarrassed or afraid to seek treatment as well. However, without treatment, it is impossible to come out of the disorder as it can be a lifelong illness.

Delusional Disorder At A Glance

  1. Delusional disorder is categorized as a psychotic disorder, where the patient can’t tell what’s real from what is imagined.
  2. A delusion is wrong or a false belief that happens due to an incorrect interpretation of reality.
  3. Constant delusions are the primary symptom of this psychotic disorder.
  4. This disorder commonly happens in middle to late life and is more prevalent in women than in men.
  5. Delusional disorder is more common in people who have family members with a similar mental health issues.
  6. Treatment catering to delusional disorder mostly includes medication and psychotherapy.
👇 References:
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  3. Corlett, P. R., Taylor, J. R., Wang, X. J., Fletcher, P. C., & Krystal, J. H. (2010). Toward a neurobiology of delusions. Progress in neurobiology, 92(3), 345–369. https://doi.org/10.1016/j.pneurobio.2010.06.007 []
  4. Fenton, W. S., McGlashan, T. H., Victor, B. J., & Blyler, C. R. (1997). Symptoms, subtype, and suicidality in patients with schizophrenia spectrum disorders. The American journal of psychiatry, 154(2), 199–204. https://doi.org/10.1176/ajp.154.2.199 []
  5. Leo, R. J., & Regno, P. D. (2000). Atypical Antipsychotic Use in the Treatment of Psychosis in Primary Care. Primary care companion to the Journal of clinical psychiatry, 2(6), 194–204. https://doi.org/10.4088/pcc.v02n0601 []
  6. Avasthi, A., Sahoo, S., & Grover, S. (2020). Clinical Practice Guidelines for Cognitive Behavioral Therapy for Psychotic Disorders. Indian journal of psychiatry, 62(Suppl 2), S251–S262. https://doi.org/10.4103/psychiatry.IndianJPsychiatry_774_19 []
  7. Serruya, G., & Grant, P. (2009). Cognitive-behavioral therapy of delusions: mental imagery within a goal-directed framework. Journal of clinical psychology, 65(8), 791–802. https://doi.org/10.1002/jclp.20616 []