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Paranoid Personality Disorder (PPD)


Mark Zimmerman

, MD, Rhode Island Hospital

Reviewed/Revised Sep 2023

Paranoid personality disorder is characterized by a pervasive pattern of unwarranted distrust and suspicion of others that involves interpreting their motives as malicious. Diagnosis is by clinical criteria. Treatment is with cognitive-behavioral therapy and sometimes medications.

Patients with paranoid personality disorder distrust others and assume that others intend to harm or deceive them, even when they have no or insufficient justification for these feelings.

There is some evidence of increased prevalence in families. Some evidence suggests a link between this disorder and emotional and/or physical abuse and victimization during childhood.

Comorbidities are common. Paranoid personality disorder is rarely the sole diagnosis. Common comorbidities include thought disorders (eg, schizophrenia Schizophrenia Schizophrenia is characterized by psychosis (loss of contact with reality), hallucinations (false perceptions), delusions (false beliefs), disorganized speech and behavior, flattened affect... read more ), anxiety disorders Overview of Anxiety Disorders Anxiety disorders are characterized by persistent and excessive fear and anxiety and the dysfunctional behavioral changes a patient may use to mitigate these feelings. Anxiety disorders are... read more (eg, social phobia [social anxiety disorder]), posttraumatic stress disorder Posttraumatic Stress Disorder (PTSD) Posttraumatic stress disorder (PTSD) is a disabling disorder that develops after exposure to a traumatic event. It is characterized by intrusive thoughts, nightmares, and flashbacks; avoidance... read more , alcohol use disorders Alcohol Toxicity and Withdrawal Alcohol (ethanol) is a central nervous system depressant. Large amounts consumed rapidly can cause respiratory depression, coma, and death. Large amounts chronically consumed damage the liver... read more , and another personality disorder (eg, borderline personality disorder Borderline Personality Disorder (BPD) Borderline personality disorder is characterized by a pervasive pattern of instability and hypersensitivity in interpersonal relationships, instability in self-image, extreme mood fluctuations... read more ).

General references

  • 1. Grant BF, Hasin DS, Stinson FS, et al: Prevalence, correlates, and disability of personality disorders in the United States: Results from the national epidemiologic survey on alcohol and related conditions. J Clin Psychiatry 65(7):948-958, 2004. doi: 10.4088/jcp.v65n0711

  • 2. Morgan TA, Zimmerman M: Epidemiology of personality disorders. In Handbook of Personality Disorders: Theory, Research, and Treatment. 2nd ed, edited by WJ Livesley, R Larstone, New York, NY: The Guilford Press, 2018, pp. 173-196.

Symptoms and Signs of Paranoid Personality Disorder

Patients with paranoid personality disorder suspect that others are planning to exploit, deceive, or harm them. They feel that they may be attacked at any time and without reason. Even though there is little or no evidence, they persist in maintaining their suspicions and thoughts.

Often, these patients think that others have greatly and irreversibly injured them. They are hypervigilant for potential insults, slights, threats, and disloyalty and look for hidden meanings in remarks and actions. They closely scrutinize others for evidence to support their suspicions. For example, they may misinterpret an offer of help as implication that they are unable to do the task on their own. If they think that they have been insulted or injured in any way, they do not forgive the person who injured them. They tend to counterattack or to become angry in response to these perceived injuries. Because they distrust others, they feel a need to be autonomous and in control.

These patients are hesitant to confide in or develop close relationships with others because they worry that the information may be used against them. They doubt the loyalty of friends and the faithfulness of their spouse or partner. They can be extremely jealous and may constantly question the activities and motives of their spouse or partner in an effort to justify their jealousy.

Patients with paranoid personality disorder often have difficulty with interpersonal relationships. When others respond negatively to them, they take these responses as confirmation of their original suspicions.

Diagnosis of Paranoid Personality Disorder

  • Diagnostic and Statistical Manual of Mental Disorders, 5th ed, Text Revision (DSM-5-TR) criteria

  • A persistent distrust and suspiciousness of others

  • Unjustified suspicion that other people are exploiting, injuring, or deceiving them

  • Preoccupation with unjustified doubts about the reliability of their friends and coworkers

  • Reluctance to confide in others lest the information be used against them

  • Misinterpretation of benign remarks or events as having hidden belittling, hostile, or threatening meaning

  • Holding of grudges for insults, injuries, or slights

  • Readiness to think that their character or reputation has been attacked and quickness to react angrily or to counterattack

  • Recurrent, unjustified suspicions that their spouse or partner is unfaithful

Also, symptoms must have begun by early adulthood.

Differential diagnosis

Clinicians can usually distinguish paranoid personality disorder from other personality disorders by the pervasiveness of its paranoia regarding others (eg, as opposed to the more transient paranoia of borderline personality) and by the core feature of each disorder:

Diagnosis reference

  • 1. American Psychiatric Association: Diagnostic and Statistical Manual of Mental Disorders, 5th ed, Text Revision (DSM-5-TR). Washington, DC, American Psychiatric Association, 2022, pp 737-741.

Treatment of Paranoid Personality Disorder

  • Cognitive-behavioral therapy

  • Sometimes medications

No treatments have been proved effective for paranoid personality disorder.

The overall high levels of suspicion and mistrust in patients make establishing rapport difficult. Expressing recognition of any validity in patients' suspicions may facilitate an alliance between patient and clinician. This alliance may then enable patients to participate in cognitive-behavioral therapy or be willing to take any medications (eg, antidepressants, atypical antipsychotics) prescribed to treat specific symptoms. Atypical (2nd-generation) antipsychotics Second-generation antipsychotics Antipsychotic drugs are divided into conventional antipsychotics and 2nd-generation antipsychotics (SGAs) based on their specific neurotransmitter receptor affinity and activity. SGAs may offer... read more may help decrease anxiety (1 Treatment reference Paranoid personality disorder is characterized by a pervasive pattern of unwarranted distrust and suspicion of others that involves interpreting their motives as malicious. Diagnosis is by clinical... read more ) though no placebo-controlled studies have established efficacy.

Treatment reference

  • 1. Birkeland SF: Psychopharmacological treatment and course in paranoid personality disorder: A case series. Int Clin Psychopharmacol 28(5):283-285, 2013. doi: 10.1097/YIC.0b013e328363f676

NOTE: This is the Professional Version. CONSUMERS: View Consumer Version
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