Paranoid Personality Disorder Fast Facts

Paranoid personality disorder (PPD) is a mental condition in which a person is unusually suspicious and mistrustful of other people without reason.

PPD affects up to 4.5% of people in the United States, making it a common personality disorder.

PPD affects men more often than women.

People who have relatives with schizophrenia or delusional disorder are at an increased risk for PPD.

Personality disorders like PPD are characterized by long-term patterns of behavior that remain consistent over time.

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PPD affects up to 4.5% of people in the United States, making it a common personality disorder.

What is Paranoid Personality Disorder?

Paranoid personality disorder (PPD) is an illness characterized by mistrust and suspicion focused on other people, even when there is no reason to be suspicious. People with PPD believe that other people intend to do them harm, and they may believe that others have harmed them in the past, even if that’s untrue. Their paranoia gets in the way of their daily functioning and impairs their ability to form healthy relationships.

PPD is one of a group of conditions called Cluster A personality disorders. This group also includes schizoid personality disorder and schizotypal personality disorder.

Symptoms of Paranoid Personality Disorder

Common symptoms of PPD include:

  • Inaccurate belief that others are trying to harm, exploit, or deceive them
  • Persistent doubts about the loyalty or motives of people close to them
  • Refusal to trust others for fear of having their vulnerabilities used against them
  • Inaccurately interpreting benign interactions as threatening or hostile
  • Holding grudges
  • Reacting angrily to perceived attacks and tendency to attack in return

What Causes Paranoid Personality Disorder?

The exact cause of PPD has not been discovered. Several factors, however, seem to put an individual at increased risk of PPD.

  • Family history and genetics. People with PPD often have a family history of schizophrenia or delusional disorder. Therefore, scientists suspect a connection between these disorders and a possible genetic component to PPD, but no definite association with any gene or group of genes has yet been discovered.
  • Childhood experiences. Some researchers believe that childhood trauma may increase the risk of PPD.

Is Paranoid Personality Disorder Hereditary?

Scientists have not yet been able to identify a specific genetic component that increases the risk of PPD. Inherited genes may increase an individual’s susceptibility to PPD, but the disorder’s actual development may result from external triggering circumstances.

How Is Paranoid Personality Disorder Detected?

In addition to their paranoid beliefs and behaviors, people with PPD may also exhibit other symptoms that are warning signs of the disorder. These other symptoms can include:

  • Secretive behavior
  • Controlling behavior
  • Argumentative behavior
  • Stubbornness
  • Sensitivity and overreaction to criticism
  • Emotional detachment
  • Jealousy
  • Consistently negative opinions of other people
  • Racism and adherence to cultural stereotypes

How Is Paranoid Personality Disorder Diagnosed?

Diagnosis of PPD begins with determining that the patient has a cluster of symptoms that meet the diagnostic criteria for the disorder. A doctor will start with a physical exam to rule out biological problems that may be causing symptoms. After these exams, if the doctor suspects that PPD or another mental disorder is the cause of the symptoms, they may recommend a psychological or psychiatric assessment to solidify the diagnosis further.

Diagnostic steps may include:

  • A physical exam. This exam will rule out physical conditions that could be causing the symptoms.
  • Psychological assessments. These assessments may take the form of questionnaires or talk sessions with a mental health professional to assess the patient’s mood, mental state, and mental health history. Family members or caregivers may also be asked to participate in these assessments.

The results of the psychological assessments will be compared to the diagnostic criteria for PPD in the Diagnostic and Statistical Manual of Mental Disorders (DSM). The DSM criteria for PPD include:

  • Broad mistrust of others that begins in adulthood.
  • At least four symptoms are present.
  • The symptoms begin by early adulthood.


How Is Paranoid Personality Disorder Treated?

There is no cure for PPD, and no medications are commonly used to treat the disorder. Psychotherapy may be helpful, but the disorder’s symptoms often get in the way of successful treatment.


People with PPD typically will not seek treatment independently because they don’t believe they have a problem. When they do enter treatment, they are unlikely to trust their therapist and may resist or stop following the treatment plan.

The most commonly used therapeutic approach is cognitive-behavioral therapy (CBT). This type of treatment focuses on teaching the patient to recognize inaccurate perceptions about themselves and others and develop strategies for dealing with these misperceptions when they occur.


In some cases, medications may help control co-existing problems such as anxiety or depression. The drugs used to treat these symptoms include selective serotonin reuptake inhibitors (SSRIs), anti-anxiety medications, and antipsychotic drugs.

How Does Paranoid Personality Disorder Progress?

People with PDD have trouble forming and maintaining relationships, and their paranoia may prevent them from functioning normally in society. As a result, they are unlikely to seek treatment, and over time, their behavior may have increasingly severe consequences.

Long-term adverse effects of PPD can include:

  • Unemployment or homelessness
  • Financial difficulties
  • Legal difficulties
  • Social isolation
  • Lack of healthy interpersonal relationships

How Is Paranoid Personality Disorder Prevented?

There is no known way to prevent PPD, but early intervention may help someone with the disorder learn to form more healthy relationships with other people.

Paranoid Personality Disorder Caregiver Tips

Many people with paranoid personality disorder also suffer from other brain and mental health-related issues, a condition called co-morbidity. Here are a few of the disorders commonly associated with PPD:

Paranoid Personality Disorder Brain Science

Because people with paranoid personality disorder rarely seek treatment and the condition almost always co-exists with other psychiatric disorders, very little research has been done on the brain-related and genetic underpinnings of PPD. When scientists have investigated PPD, it has primarily been in connection with schizophrenia and other similar personality disorders.

One case study has suggested that brain damage caused by traumatic injuries or substance abuse may play a role in the symptoms of PPD in some people. In the case described, a male patient with a history of concussion and alcohol abuse exhibited signs of paranoia (and jealousy in particular). In addition, the symptoms worsened during periods of alcohol abuse. However, no further definitive connection between PPD and brain trauma has been established.

Paranoid Personality Disorder Research

Title: Face Your Fears: Cognitive Behavioral Virtual Reality Therapy for Paranoia (FYF)

Stage: Recruiting

Contact: Ulrik N. Jeppesen, MD

Copenhagen Research Center for Mental Health

Copenhagen, Denmark 

Paranoid ideations and ideas of reference are among the most frequent symptoms of psychotic disorders. They hinder patients from conducting daily activities such as leaving the home or using public transportation and immensely influence their quality of life. The social avoidance caused by these symptoms does not improve with antipsychotic mediation. Cognitive-behavioral therapy (CBT) for psychosis has demonstrated a beneficial effect on psychotic symptoms, but the average effect sizes are in the small to moderate range, and training and resource requirements mean that, in practice, therapy is not delivered to all those who might benefit. Hence, there is considerable interest in developing novel therapies that draw on the principles of cognitive-behavioral therapy for psychosis but are shorter, more effective, and capable of being delivered by a broader workforce. Augmenting CBT with virtual reality exposure can create artificial experiences in real-time that make the user feel immersed and able to interact as if it was the real world.

Additionally, virtual reality therapy allows for the personalization of the therapy to match the specific social challenges of each patient. Preliminary findings suggest virtual reality exposure leads to faster symptom reduction than traditional therapy. While the potential beneficial effects of virtual reality exposure to psychotic, and sub-threshold psychotic symptoms, such as paranoid ideations and ideas of reference, are evident and virtual reality therapies are promising in general, the research field is in urgent need of evidence on the effectiveness of virtual reality therapy in patients with schizophrenia spectrum disorders. The proposed trial is, to date, the largest trial in the world to evaluate the effectiveness of cognitive-behavioral virtual reality therapy (CBT-VR) compared to traditional CBT. The investigators expect CBT-VR to be more beneficial in reducing paranoid ideations and ideas of reference in patients with schizophrenia spectrum disorders.

Additionally, the investigators expect it to improve depressive, anxiety, and negative symptoms, social cognition, psychosocial functioning, and quality of life in patients with schizophrenia spectrum disorders. The target group in the trial also encompasses patients with schizotypal disorder (often young adults), showing subthreshold psychotic symptoms (e.g., ideas of reference) that are at increased risk of developing manifest psychosis. The CBT-VR may show efficacy in preventing progression to an overt psychotic state in these patients. Hence, there is great potential for CBT-VR in treating patients with psychosis and sub-threshold psychosis, but studies are needed to establish evidence for the treatment. If the current trial results are positive, the manualized treatment can easily be implemented in clinical practice.

Title: Brain Imaging in Early Psychosis

Stage: Enrolling by invitation

Washington University School of Medicine

Saint Louis, MO 

Schizophrenia is a devastating illness inflicting about 1% of the population worldwide. Symptoms of schizophrenia include paranoia, hallucinations, and disorganized behaviors and are associated with lifelong occupational and social disability. It typically develops in adolescence or early adulthood, particularly formative periods when significant educational, vocational, and social life changes occur. Then, the brain undergoes a rearrangement of critical neural circuits. The “prodrome” is the period before the onset of a psychotic disorder, like schizophrenia. Prodromal youth often have significant emotional distress and social withdrawal, and family members may observe a concerning change in behavior or school or work performance. Identifying those at clinical high risk for a psychotic disorder is important, as early intervention can improve symptoms and functioning and could prevent the eventual development of a psychotic disorder. This study will focus on individuals aged 13-25 years who have met the criteria for a psychosis-risk syndrome (or attenuated psychosis syndrome) or are at a very early stage (first three years after diagnosis) of a psychotic disorder, such as schizophrenia or schizoaffective disorder. Involvement will be either 2 or 3 partial days at Washington University and will involve approximately 3 hours of MRI scanning and up to 6 hours of behavioral testing. Additionally, the investigators will study the effect of genetics on the patterns of brain connectivity in various psychiatric populations. DNA will be collected non-invasively from saliva and stored and processed in Washington University facilities.


Title: Compassion and Metacognition in Schizotypal Personality (CMBT)

Stage: Recruiting

Principal Investigator: Simone Cheli

Tages Onlus

Florence, Italy 

The purpose of this study is to assess the safety and efficacy of a newly developed psychotherapy for schizotypal personality disorder. This new form of psychotherapy integrates compassion-focused therapy and metacognitively oriented psychotherapy.

After being informed about the study and potential risks, all patients giving written informed consent will undergo a psychological assessment to determine eligibility for study entry. Patients who meet the eligibility requirements will be randomized in a double-blind manner in a 1:1 ratio to new integrative psychotherapy or treatment as usual (cognitive behavioral therapy plus standard psychopharmacological treatment). One month after the conclusion of the two forms of treatment (both lasting six months), patients will have access to the final follow-up assessment.

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