Shared Psychotic Disorder

Shared Psychotic Disorder

Shared Psychotic Disorder

Shared psychotic disorder (now termed “other specified schizophrenia spectrum” and “other psychotic disorder” in the DSM-5) is when a delusional belief is shared from one person to another or others.

Most common in nuclear family relationships, folie a deux is when two people share the delusional belief, folie à trois when three people share, it and so on. An entire family can share a delusional belief, in which case the condition is referred to as folie en famille or family madness.

A delusion is a fixed, false belief held with absolute certainty despite strong evidence to the contrary. The belief is also inconsistent with the cultural and religious norms of the affected individual(s), e.g., aliens are stalking your girlfriend or the end of the world will happen next week.

If a large number of people believe the same false information and it generates acute anxiety in most members of the group, it is referred to as mass hysteria rather than shared psychotic disorder.

Prevalence

The chances of developing a shared psychotic disorder are highest if in a cult. Otherwise the disorder is rare.

Symptoms of Shared Psychotic Disorders:

Shared Psychotic, along with Cotard’s Syndrome, and Capgras Syndrome are in a category of rare disorders. Shared psychotic differs because its symptoms present in two people, and the person with the delusion(s) is usually the dominant person in the long-term relationship and the people sharing the delusion are usually the passive ones.

A common element observed in people with shared psychotic disorder is social isolation, and usually, one individual has the primary psychosis, while the other person who shares it can often have elements of dependent personality disorder. Signs and symptoms include:

  • Impaired health, mental health, and social wellbeing from the stress of believing the delusion
  • Ensuing depression, acute anxiety, and aggressive behavior
  • Social isolation

If not treated, shared psychotic disorder can cause impairment in functioning at home, work, school, or social settings. It often exists with other conditions such as major depressive disorder or generalized anxiety disorder.

Causes of Shared Psychotic Disorders:

The exact causes of shared anxiety disorder remain unknown; however, certain factors have been implicated.


  • Environmental – stress, social isolation, influence of the person with the psychotic disorder on the person(s) sharing the delusion, poor work-related and social functioning skills
  • Mental health – existing dependant personality disorder
  • Genetic – a relative with a psychotic disorder

Diagnosing Shared Psychotic Disorders:

There is no proven lab work or brain scan that can accurately diagnose shared psychotic disorder, so diagnosis is made on the person’s response to questions and their mental health history. This diagnosis is only given after any possible medical illnesses or substance abuse is ruled out.

DSM-5 puts shared psychotic disorder into the category of “other specified schizophrenia spectrum and other psychotic disorder,” saying a diagnosis can be made for this if:

Delusional symptoms in partner of individual with delusional disorder: In the context of a relationship, the delusional material from the dominant partner provides content for delusional belief by the individual who may not otherwise entirely meet criteria for delusional disorder.

Shared psychotic disorder is usually diagnosed when the two or more people who share the belief live near one another and they are socially and/or physically isolated from society. A dominant person with a psychotic disorder forms a delusional belief during an episode and persuades another person or persons it is true.

There are several types of delusions that are transmitted from one person to another in a shared psychotic disorder. These include:

  • Bizarre delusions – beliefs that are obviously unbelievable and not understood and accepted by others in the same religion or culture, such as the person is secretly being filmed going about life and millions are watching.
  • Non-bizarre delusions – beliefs that are realistic and are understood and accepted by others in the same religion or culture, such as a partner poisoning their meals.

Delusions can be further categorized by whether they are mood-congruent (the delusions match the person’s mood) or mood incongruent (they do not).

Treatment for Shared Psychotic Disorder:

Because the delusion is a fixed belief, it can be difficult to treat a person with shared psychotic disorder. The best results occur when the person believing the shared delusion ends contact with the person who has the psychotic illness.

Treatment includes:

  • Psychotherapy

    • Family education and support – provides support, education, and relational skills classes for the person and family members. Skills are then taught re reducing the influence of the person with delusions within the family unit and how to support him/her through treatment for the psychotic disorder.
    • Metacognitive training – focuses particularly on the thought processes that lead to adopting the delusions to correct them.
  • Medication
    Meds may be required if separation and therapy aren’t effective in ending the shared delusion.

    • Atypical antipsychotics – such as olanzapine and clozapine to block dopamine receptors or combine antagonism of dopamine and serotonin
    • Phenothiazine antipsychotics – such as thioridazine and chlorpromazine to block dopamine and serotonin receptors in the brain and depress certain hormone releases
  • Hospitalization
    Hospitalization is required if symptoms are severe and/or there are concerns regarding the safety of those affected and/or others.

    If the people involved are admitted to hospital separately, then the delusions in the person with the induced beliefs usually resolve without the need of medication.

Symptoms of Shared Psychotic Disorders:

Shared Psychotic, along with Cotard’s Syndrome, and Capgras Syndrome are in a category of rare disorders. Shared psychotic differs because its symptoms present in two people, and the person with the delusion(s) is usually the dominant person in the long-term relationship and the people sharing the delusion are usually the passive ones.

A common element observed in people with shared psychotic disorder is social isolation, and usually, one individual has the primary psychosis, while the other person who shares it can often have elements of dependent personality disorder. Signs and symptoms include:

  • Impaired health, mental health, and social wellbeing from the stress of believing the delusion
  • Ensuing depression, acute anxiety, and aggressive behavior
  • Social isolation

If not treated, shared psychotic disorder can cause impairment in functioning at home, work, school, or social settings. It often exists with other conditions such as major depressive disorder or generalized anxiety disorder.

Causes of Shared Psychotic Disorders:

The exact causes of shared anxiety disorder remain unknown; however, certain factors have been implicated.


  • Environmental – stress, social isolation, influence of the person with the psychotic disorder on the person(s) sharing the delusion, poor work-related and social functioning skills
  • Mental health – existing dependant personality disorder
  • Genetic – a relative with a psychotic disorder

Diagnosing Shared Psychotic Disorders:

There is no proven lab work or brain scan that can accurately diagnose shared psychotic disorder, so diagnosis is made on the person’s response to questions and their mental health history. This diagnosis is only given after any possible medical illnesses or substance abuse is ruled out.

DSM-5 puts shared psychotic disorder into the category of “other specified schizophrenia spectrum and other psychotic disorder,” saying a diagnosis can be made for this if:

Delusional symptoms in partner of individual with delusional disorder: In the context of a relationship, the delusional material from the dominant partner provides content for delusional belief by the individual who may not otherwise entirely meet criteria for delusional disorder.

Shared psychotic disorder is usually diagnosed when the two or more people who share the belief live near one another and they are socially and/or physically isolated from society. A dominant person with a psychotic disorder forms a delusional belief during an episode and persuades another person or persons it is true.

There are several types of delusions that are transmitted from one person to another in a shared psychotic disorder. These include:

  • Bizarre delusions – beliefs that are obviously unbelievable and not understood and accepted by others in the same religion or culture, such as the person is secretly being filmed going about life and millions are watching.
  • Non-bizarre delusions – beliefs that are realistic and are understood and accepted by others in the same religion or culture, such as a partner poisoning their meals.

Delusions can be further categorized by whether they are mood-congruent (the delusions match the person’s mood) or mood incongruent (they do not).

Treatment for Shared Psychotic Disorder:

Because the delusion is a fixed belief, it can be difficult to treat a person with shared psychotic disorder. The best results occur when the person believing the shared delusion ends contact with the person who has the psychotic illness.

Treatment includes:

  • Psychotherapy

    • Family education and support – provides support, education, and relational skills classes for the person and family members. Skills are then taught re reducing the influence of the person with delusions within the family unit and how to support him/her through treatment for the psychotic disorder.
    • Metacognitive training – focuses particularly on the thought processes that lead to adopting the delusions to correct them.
  • Medication
    Meds may be required if separation and therapy aren’t effective in ending the shared delusion.

    • Atypical antipsychotics – such as olanzapine and clozapine to block dopamine receptors or combine antagonism of dopamine and serotonin
    • Phenothiazine antipsychotics – such as thioridazine and chlorpromazine to block dopamine and serotonin receptors in the brain and depress certain hormone releases
  • Hospitalization
    Hospitalization is required if symptoms are severe and/or there are concerns regarding the safety of those affected and/or others.

    If the people involved are admitted to hospital separately, then the delusions in the person with the induced beliefs usually resolve without the need of medication.

Sources MENTALHELP.net – Symptoms of Shared Psychotic Disorder | DISORDERS – Shared Psychotic Disorder | NIH – The nosological significance of Folie à Deux | PSYCHOLOGY TODAY – Delusional Disorder | NEWS MEDICAL – Delusion Types | MENTAL HEALTH DAILY – 4 Types of Delusions & Extensive List of Themes | ACCUTERM – 15 Truly Bizarre Mental Delusions | PSYCH CENTRAL – Dependent Personality Disorder Symptoms | Kelly, J.R.; Iannone, R.E.; McCarty, M.K. (2014). “The function of shared affect in groups”. In von Scheve, Christian; Salmella, Mikko (eds.). Collective Emotions. OUP Oxford.