Shared Psychotic Disorder: Information, Symptoms, Treatment and More

Shared Psychotic Disorder is a rare, yet serious mental health condition that involves an individual imposing a delusional belief onto someone else.

The condition is also known as Shared Psychosis, or Folie á deux. A delusion is a false belief that an individual stringently believes in. The person who initially has a delusion (inducer) will often have a close relationship with the person who starts to develop the same delusion.

The inducer will often believe they are helping the person involved by sharing their belief. As well as delusions, hallucinations can occasionally be passed on as well. This is a serious condition, and can cause distress for all involved.

Treatment is available for the disorder. Accessing treatment is important due to the risk of the symptoms exacerbating further.

What are the symptoms of Shared Psychotic Disorder?

The inducer will commonly have a pre-existing mental health condition that causes their delusions. This may be Schizophrenia, Delusional Disorder or Paranoid Personality Disorder among others. The key symptom is delusions.

Delusions

A delusion is where an individual has a belief that they believe steadfastly in, though isn’t true. The person involved will be adamant that their belief is true. In the majority of cases however, they will not be correct.

Delusions can take on a wide array of forms. An example of a delusion is paranoia – such as the feeling an individual is being spied on. As such, the delusion can have a marked effect on the day-to-day life of the individual.

Examples of delusions are paranoia, believing people on TV are communicating hidden messages to an individual, or that a celebrity is trying to make contact with the person.

The inducer will normally spend a lot of time with the affected person. They will commonly have a close relationship, and the inducer will be the more ‘dominant’ person in the relationship.

When the two people spend significant amounts of time with each other in social isolation, the risk is amplified.

The affected person will begin to believe the delusion of the other person, but will otherwise be healthy. They will commonly be a rather passive person. As time goes by, their belief in the delusion will strengthen, making it harder to treat.

But when separated from the inducer, the affected person will normally stop believing the delusion.

In some cases, it is possible that more than two people can be affected. This may happen in a small family, or in a cult.

It is common for delusions to have a strong influence on the life of the two people. If paranoid, the duo may start to suspect others in the local community. They may act aggressively when questioned about the nature of their belief.

It is also possible for hallucinations to be imposed on another individual, however this is incredibly rare.  

What are the causes of Shared Psychotic Disorder?

The cause of Shared Psychotic Disorder isn’t known. Most suspect that rather than there being just one cause, a range of factors may contribute to its onset.

Circumstance and personality traits appear to be a key consideration. Generally, the affected person will be passive and open to suggestion from other people. If they are combined with someone who does suffer from delusions, then this may be a toxic mix.

Isolation from others, which means the affected individual only has one opinion to listen to, can be another factor. Spending a long time in close proximity to someone else typically results in trust, and leads the affected individual to be likelier to believe delusions.

In any case, it is likely that the affected individual is predisposed genetically to mental illness, which may make them vulnerable.

Sometimes though, there is simply no attributable cause – it isn’t always clear. But in many cases, certain circumstances and personality traits are conducive for causing the disorder.  

Diagnosis of Shared Psychotic Disorder

Because the people affected by Shared Psychotic Disorder will normally be socially isolated, it can be difficult for others to raise the alarm.

Therefore, it may take them a long time to access treatment. However, the inducer will often be receiving psychiatric help for their symptoms.

It is possible that the other person’s symptoms will be noticed during a routine appointment. Sometimes, if an individual engages in bizarre behaviour, law enforcement officials may notice the person.

Shared Psychotic Disorder is normally relatively simple to diagnose, as long as the evidence linking the two individuals is clear. The affected individual will often be referred to a mental health specialist.

The mental health specialist will consequently conduct a thorough assessment on the individual, and aim to make a diagnosis.  

For Shared Psychotic Disorder to be diagnosed, the following criteria should be generally met:

• The delusion was not caused by substance abuse, or as an unwanted side effect of a medication.
• The affected individual develops a delusion that can be linked to a close relationship with another person who already has a delusion
• This delusion is similar, or exactly the same, as that of the individual who has induced the delusion.
• The delusion cannot be attributed to a symptom of an alternative psychotic disorder such as Schizophrenia or Psychotic Depression.

How is Shared Psychotic Disorder treated?

It is important to treat Shared Psychotic Disorder. If left untreated, it may exacerbate and become a more severe psychotic disorder. Treatment is available, and a full recovery is possible.

At first, an individual should be separated from the inducer. This in many cases will result in the delusion being stopped, and the person returning to full health.

Sometimes though, especially in long-term cases, this doesn’t always happen, with treatment requires. Treatment normally includes:

Talking Therapy

Some form of talking therapy can prove useful with Shared Psychotic Disorder. It is normally recommended that the Socratic questioning technique is adopted for use in any delusion-related disorder – which involves asking open-ended questions.

This is because it may lead an individual to realise there is no evidence for their beliefs. Sometimes, therapy can take place in families – especially if two members of a family need to be kept separated from one another.

Family Therapy: Family therapy is a form of therapy that is delivered with close family members. The therapy can focus on how a person’s actions have caused problems for their wider family. In many cases, the family will be told not to condone nor reward behaviour that is associated with their problematic behaviour. In theory, by seeing the damage their behaviour can cause, this can help the individual change their behaviour.

Psychoanalytical Psychotherapy: Psychoanalytical Psychotherapy is a talking therapy that aims to help uncover and resolve unconscious beliefs that cause psychiatric conditions. Traumatic experiences that may or may not be buried in the unconscious mind can be highlighted and processed. Psychoanalytical psychotherapy involves talking to a trained therapist. The therapist can show the individual how early memories and past traumas have affected their thinking, behaviour and attitude in the modern day. Psychoanalytical psychotherapy is especially useful for any condition that involves past trauma. Renowned neurologist Sigmund Freud developed this therapy, which is typically completed over a long-term basis.

These are just two examples, with there also being a huge range of other types of talking therapies, with these therapies being able to help in many ways. We have more information on our Therapy section.

Medication

Antipsychotics may be prescribed in the short-term, as they can help with the symptoms they are displaying. Moreover, it can also increase the likelihood of talking therapy working.  

Antipsychotics: Antipsychotics (also known as neuroleptics) block the effect of dopamine – a chemical in the brain that is heavily linked to psychotic symptoms like hallucinations. They can also be useful for stabilising mood, and treating anxiety. They are not suitable for everyone however, and are often associated with many side effects like weight gain, dizziness and dry mouth.

Other

Hospitalisation sometimes occurs in Shared Psychotic Disorder. This happens when those involved are seen as a danger to themselves or others.

Summary

It is important that anyone who may be suffering from Shared Psychotic Disorder receives treatment to help them. There have been many harrowing cases involving this condition that has caused so much destruction.

The condition generally gets worse over time, and can lead to substantial distress for all involved. Treatment can help, and should lead to the individual recovering, and returning to their healthy ways.

See Also

• Psychosis Section
• What is the Prognosis for Psychosis?
• Therapy Homepage
• Medicine Homepage