Causes

The causes of paranoid personality disorder are unknown. The disorder appears to be more common in families with psychotic disorders such as schizophrenia and delusional disorder, which suggests genes may be involved. However, environmental factors may play a role, as well.

The condition appears to be more common in men.

Symptoms

People with paranoid personality disorder are highly suspicious of other people. As a result, people with this condition severely limit their social lives.

They often feel that they are in danger, and look for evidence to support their suspicions. People with this disorder have trouble seeing that their distrustfulness is out of proportion to their environment.

Common symptoms include:

• Concern that other people have hidden motives
• Expectation that they will be exploited by others
• Inability to work together with others
• Social isolation
• Detachment
• Hostility

Exams and Tests

Like other personality disorders, paranoid personality disorder is diagnosed based on a psychological evaluation and the history and severity of the symptoms.

Treatment

Treatment is difficult because people with this condition are often very suspicious of doctors. If treatment is accepted, talk therapy and medications can often be effective.

Outlook (Prognosis)

The outlook usually depends on whether the person is willing to accept help. Therapy and medications can reduce paranoia and limit its impact on the person's daily functioning.

Possible Complications

• Extreme social isolation
• Interference with work

When to Contact a Medical Professional

If suspicions are interfering with your relationships or work, contact a health care provider or mental health professional.

Alternative Names

Personality disorder - paranoid

References

Blais MA, Smallwood P, Groves JE, Rivas-Vazquez RA. Personality and personality disorders. In: Stern TA, Rosenbaum JF, Fava M, Biederman J, Rauch SL, eds. Massachusetts General Hospital Comprehensive Clinical Psychiatry. 1st ed. Philadelphia, Pa: Mosby Elsevier;2008:chap 39.

Updated: 4/14/2012

Reviewed by: Linda Vorvick, MD, Medical Director, MEDEX Northwest Division of Physician Assistant Studies, University of Washington School of Medicine; David B. Merrill, MD, Assistant Clinical Professor of Psychiatry, Department of Psychiatry, Columbia University Medical Center, New York, NY. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.