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Overview of Personality Disorders


Mark Zimmerman

, MD, Rhode Island Hospital

Full review/revision May 2021 | Modified Sep 2022
Topic Resources

Personality disorders are long-lasting, pervasive patterns of thinking, perceiving, reacting, and relating that cause the person significant distress and/or impair the person's ability to function.

  • There are 10 types of personality disorders, and each has characteristic problems with self-image and patterns of response to others and to stressful events.

  • Symptoms are different depending on the type of personality disorder, but in general, people have difficulty relating to others and handling stress and/or have a self-image that varies depending on the situation and that differs from how others perceive them.

  • Doctors consider diagnosing a personality disorder when people persistently view themselves or others in ways that differ from reality or when they continue to act in ways that routinely have negative consequences.

  • Drugs prescribed to treat personality disorders usually do not change those disorders but may help lessen distressing symptoms.

  • Psychotherapy may help people become aware of their role in creating their problems and help them change their socially undesirable behavior.

Personality traits represent patterns of thinking, perceiving, reacting, and relating that are relatively stable over time. For example, some people tend to be moody and withdrawn. Others tend to be outgoing and social.

Personality disorders exist when people's personality traits become so pronounced, rigid, and maladaptive that the person has problems at work, at school, and/or in dealing with other people. These social maladaptations can cause significant distress in people with personality disorders and in those around them. Most people whose personality traits are ineffective or produce negative consequences try to change their response patterns. In contrast, people with a personality disorder do not change their response patterns even when these patterns are repeatedly ineffective and the consequences are negative. Such patterns are called maladaptive because people do not adjust (adapt) as circumstances require. Maladaptive patterns vary in how severe they are and how long they persist.

About 10% of people have a personality disorder. These disorders usually affect men and women equally, although some types of personality disorder affect one sex more than the other. For example, antisocial personality disorder is 6 times more common among men.

For most people with a personality disorder, the disorder causes moderate problems and lessens over time. However, some people have severe social and psychologic problems that last a lifetime.

Many people with a personality disorder also have one or more of the following:

Having a personality disorder and one of these other disorders makes people less likely to respond to treatment for either disorder and thus worsens their prognosis.

Causes of Personality Disorders

Personality disorders result from the interaction of genes and environment. That is, some people are born with a genetic tendency to have a personality disorder, and this tendency is then suppressed or enhanced by environmental factors. Generally, genes and environment contribute about equally to the development of personality disorders.

Types of Personality Disorders

The 10 personality disorders can be grouped into three clusters (A, B, and C). The types in each cluster share certain basic personality traits, but each disorder has its own distinguishing features.

Cluster A is characterized by appearing odd or eccentric. It includes the following personality disorders, each with its distinguishing features:

Overview of Cluster A Personality Disorders

Cluster B is characterized by appearing dramatic, emotional, or erratic. It includes the following personality disorders, each with its distinguishing features:

Overview of Cluster B Personality Disorders

Cluster C is characterized by appearing anxious or fearful. It includes the following personality disorders, each with its distinguishing features:

Overview of Cluster C Personality Disorders

Symptoms of Personality Disorders

Personality disorders involve mainly problems with

  • Identity and a sense of self: People with a personality disorder lack a clear or stable image of themselves. That is, how they view themselves changes depending on the situation and the people they are with. For example, they may alternate between thinking of themselves as cruel or kind. Or they may be inconsistent in their values and goals. For example, they may be deeply religious while in church but irreverent and disrespectful elsewhere. Self-esteem may be unrealistically high or low.

  • Relationships: People with a personality disorder struggle to form close, stable relationships with others. They may be insensitive to others or emotionally detached, or they may lack empathy.

People with a personality disorder often seem inconsistent, confusing, and frustrating to family members and other people around them, including doctors. Their parenting style may be inconsistent, detached, overemotional, abusive, or irresponsible and sometimes causes physical and/or mental problems in their children.

People with a personality disorder may have problems knowing what are reasonable, safe, and acceptable ways to treat and to behave around others.

People with a personality disorder may be unaware of their role in creating their problems.

Did You Know...

  • People with a personality disorder may not think there is any problem with their thinking or behavior.

Diagnosis of Personality Disorders

  • A doctor's evaluation, based on specific criteria

Doctors base the diagnosis of a specific personality disorder on lists of personality traits (criteria) provided for each disorder in the DSM-5.

Some people with a personality disorder are distressed by their behavior and actively seek treatment. Others cannot see a problem with their own behavior. Thus, they tend not to seek help on their own. Instead, they may be referred by their friends, family members, or a social agency because their behavior is causing difficulty for others.

When people with a personality disorder seek help, the reason is likely to be to get help with symptoms such as anxiety Symptoms Anxiety is a feeling of nervousness, worry, or unease that is a normal human experience. It is also present in a wide range of psychiatric disorders, including generalized anxiety disorder,... read more , depression Symptoms A short discussion of prolonged grief disorder. Depression is a feeling of sadness and/or a decreased interest or pleasure in activities that becomes a disorder when it is intense enough to... read more , or substance use Substance Use Disorders Substance use disorders generally involve behavior patterns in which people continue to use a substance (for example, a recreational drug) despite having problems caused by its use. The substances... read more or with the problems created by their personality disorder such as divorce, unemployment, or loneliness—rather than the disorder itself. When people report such symptoms or problems, doctors usually ask them questions to determine whether a personality disorder might be involved. For example, doctors ask how they view themselves and others and how they respond when people react negatively to their behavior. Personality disorders are underdiagnosed because doctors sometimes focus on the symptoms of anxiety or depression, which may overshadow the features of any underlying personality disorder.

The doctor suspects a personality disorder if people

  • Persist in viewing themselves or others in ways that differ from reality

  • Describe a pattern of inappropriate thoughts or behavior that they do not change despite the negative consequences of such behavior

  • Are distressed by their behavior and/or its consequences or cannot function adequately because of their behavior

The inappropriate thoughts and behaviors may involve how people see and understand themselves and others, how they interact with others, and/or how well they control their impulses. Such thoughts and behaviors are considered a disorder only if they are persistent (not just once in a while) and if a person keeps doing them even though they cause the person distress or difficulties in daily life. Also, the thoughts and behaviors must have started during adolescence or early adulthood, not later in life.

To help confirm the diagnosis, doctors may talk with the person's friends and family members to obtain additional information. Without such help, the doctor and the person might remain unaware of the person's role in creating the problems.

Treatment of Personality Disorders

  • Psychotherapy

Treatment of personality disorders is with psychotherapy, which includes individual psychotherapy and group therapy. Therapy is more likely to be effective when people seek treatment and are motivated to change.

Personality disorders can be particularly difficult to treat, so it is important to choose a therapist who is experienced and nonjudgmental and who can understand the person's self-image, areas of sensitivity, and usual ways of coping.

General principles of treatment

Although specific treatments differ according to the type of personality disorder, treatment, in general, aims to

  • Reduce distress

  • Help people understand that their problems are internal (not caused by other people or situations)

  • Decrease maladaptive and socially undesirable behavior

  • Modify the personality traits that are causing difficulties

Reducing immediate distress, such as anxiety and depression, is the first goal of treatment. Reducing distress makes treatment of the personality disorder easier. First, therapists help people identify what is causing distress. Then, they consider ways to relieve it. Therapists provide strategies to help the person get out of highly distressing situations or relationships (called psychosocial support). These strategies may include care and support by family members, friends, neighbors, health care practitioners, and others. Drugs for anxiety Treatment Anxiety is a feeling of nervousness, worry, or unease that is a normal human experience. It is also present in a wide range of psychiatric disorders, including generalized anxiety disorder,... read more or depression Drug Treatment for Depression Agomelatine, a new type of antidepressant, is a possible treatment for major depressive episodes. Several types of drugs can be used to treat depression: Selective serotonin reuptake inhibitors... read more can help relieve these symptoms. When drugs are used, they are ideally used in small doses and for a limited time.

Helping people understand that their problems are internal is crucial because people with a personality disorder may not see a problem with their own behavior. Doctors try to help people understand when their behavior is inappropriate and has harmful consequences. By establishing a cooperative, mutually respectful doctor-patient relationship, doctors can help people become more aware of themselves and recognize their socially undesirable, inappropriate behavior. Doctors can also help people realize that changes in their behavior and view of themselves and others will take time and effort.

Maladaptive and undesirable behaviors (such as recklessness, social isolation, lack of assertiveness, and temper outbursts) should be dealt with quickly to minimize ongoing damage to jobs and relationships. Sometimes doctors need to set limits on behavior in their office. For example, doctors may tell people that yelling and threatening makes conducting a session difficult. If behavior is extreme—for example, if people are reckless, isolate themselves socially, have outbursts of anger, or are self-destructive—they may need treatment at a day hospital or in a residential institution.

Changes in behavior are most important for people with one of the following personality disorders:

Group therapy and behavioral modification can typically improve behavior within months. Self-help groups or family therapy can also help change inappropriate behavior. The involvement of family members is helpful and often essential because they can act in ways that either reinforce or diminish the inappropriate behavior or thoughts.

Modifying problematic personality traits (such as dependency, distrust, arrogance, and manipulativeness) takes a long time, typically more than a year. The key to modifying these traits is

  • Individual psychotherapy

Psychotherapy Psychotherapy Extraordinary advances have been made in the treatment of mental illness. As a result, many mental health disorders can now be treated nearly as successfully as physical disorders. Most treatment... read more can help people understand how their personality disorder relates to their current problems. It can also help people learn new and better ways of interacting and coping. Usually, change is gradual.

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