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Borderline Personality Disorder (BPD)


Mark Zimmerman

, MD, Rhode Island Hospital

Reviewed/Revised May 2021 | Modified Sep 2022
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Borderline personality disorder is characterized by a pervasive pattern of instability and hypersensitivity in interpersonal relationships, instability in self-image, extreme mood fluctuations, and impulsivity. Diagnosis is by clinical criteria. Treatment is with psychotherapy and drugs.

Patients with borderline personality disorder have an intolerance of being alone; they make frantic efforts to avoid abandonment and generate crises, such as making suicidal gestures Suicidal Behavior Suicide is death caused by an intentional act of self-harm that is designed to be lethal. Suicidal behavior encompasses a spectrum of behavior from suicide attempt and preparatory behaviors... read more in a way that invites rescue and caregiving by others.

Reported prevalence of borderline personality disorder in the US varies. The estimated median prevalence is 1.6% but may be as high as 5.9%. In patients being treated as inpatients for mental health disorders, prevalence is about 20%. About 75% of patients diagnosed with this disorder are female, but in the general US population, the ratio of men to women is 1:1.

Etiology of BPD

Stresses during early childhood may contribute to the development of borderline personality disorder. A childhood history of physical and sexual abuse, neglect, separation from caregivers, and/or loss of a parent is common among patients with borderline personality disorder.

Certain people may have a genetic tendency to have pathologic responses to environmental life stresses, and borderline personality disorder clearly appears to have a heritable component. First-degree relatives of patients with borderline personality disorder are 5 times more likely to have the disorder than the general population.

Disturbances in regulatory functions of the brain and neuropeptide systems may also contribute but are not present in all patients with borderline personality disorder.

Symptoms and Signs of BPD

When patients with borderline personality disorder feel that they are being abandoned or neglected, they feel intense fear or anger. For example, they may become panicky or furious when someone important to them is a few minutes late or cancels an engagement. They think that this abandonment means that they are bad. They fear abandonment partly because they do not want to be alone.

These patients tend to change their view of others abruptly and dramatically. They may idealize a potential caregiver or lover early in the relationship, demand to spend a lot of time together, and share everything. Suddenly, they may feel that the person does not care enough, and they become disillusioned; then they may belittle or become angry with the person. This shift from idealization to devaluation reflects black-and-white thinking (splitting, polarization of good and bad).

Patients with borderline personality disorder can empathize with and care for a person but only if they feel that another person will be there for them whenever needed.

Patients with this disorder have difficulty controlling their anger and often become inappropriate and intensely angry. They may express their anger with biting sarcasm, bitterness, or angry tirades, often directed at their caregiver or lover for neglect or abandonment. After the outburst, they often feel ashamed and guilty, reinforcing their feeling of being bad.

Patients with borderline personality disorder may also abruptly and dramatically change their self-image, shown by suddenly changing their goals, values, opinions, careers, or friends. They may be needy one minute and righteously angry about being mistreated the next. Although they usually see themselves as bad, they sometimes feel that they do not exist at all—eg, when they do not have someone who cares for them. They often feel empty inside.

The changes in mood (eg, intense dysphoria, irritability, anxiety) usually last only a few hours and rarely last more than a few days; they may reflect the extreme sensitivity to interpersonal stresses in patients with borderline personality disorder.

Patients with borderline personality disorder often sabotage themselves when they are about to reach a goal. For example, they may drop out of school just before graduation, or they may ruin a promising relationship.

Impulsivity leading to self-harm is common. These patients may gamble, engage in unsafe sex, binge eat, drive recklessly, abuse substances, or overspend. Suicidal behaviors Suicidal Behavior Suicide is death caused by an intentional act of self-harm that is designed to be lethal. Suicidal behavior encompasses a spectrum of behavior from suicide attempt and preparatory behaviors... read more , gestures, and threats and self-mutilation Nonsuicidal Self-Injury (NSSI) Nonsuicidal self-injury is a self-inflicted act that causes pain or superficial damage but is not intended to cause death. Although the methods used sometimes overlap with those of suicide attempts... read more (eg, cutting, burning) are very common. Although many of these self-destructive acts are not intended to end life, risk of suicide in these patients is 40 times that of the general population. About 8 to 10% of these patients die by suicide. These self-destructive acts are usually triggered by rejection by, possible abandonment by, or disappointment in a caregiver or lover. Patients may self-mutilate to compensate for their being bad, to reaffirm their ability to feel during a dissociative episode Overview of Dissociative Disorders Many people occasionally experience a failure in the normal automatic integration of memories, perceptions, identity, and consciousness. For example, people may drive somewhere and then realize... read more , or to distract from painful emotions.

Dissociative episodes, paranoid thoughts, and sometimes psychotic-like symptoms (eg, hallucinations, ideas of reference) may be triggered by extreme stress, usually fear of abandonment, whether real or imagined. These symptoms are temporary and usually not severe enough to be considered a separate disorder.

Symptoms lessen in most patients; relapse rate is low. However, functional status does not usually improve as much as the symptoms.

Diagnosis of BPD

  • Clinical criteria (Diagnostic and Statistical Manual of Mental Disorders, Fifth Edition [DSM-5])

For a diagnosis of borderline personality disorder, patients must have

  • A persistent pattern of unstable relationships, self-image, and emotions (ie, emotional dysregulation) and pronounced impulsivity

This persistent pattern is shown by 5 of the following:

Also, symptoms must have begun by early adulthood but can occur during adolescence.

Differential diagnosis

Borderline personality disorder is most commonly misdiagnosed as

Other personality disorders share similar manifestations.

Differential diagnosis for borderline personality disorder also includes

Many disorders in the differential diagnosis of borderline personality disorder coexist with it.

Treatment of BPD

  • Psychotherapy

  • Drugs

Identifying and treating coexisting disorders is important for effective treatment of borderline personality disorder.


The main treatment for borderline personality disorder is psychotherapy.

Many psychotherapeutic interventions are effective in reducing suicidal behaviors, ameliorating depression, and improving function in patients with this disorder.

Cognitive-behavioral therapy focuses on emotional dysregulation and lack of social skills. It includes the following:

  • Dialectical behavioral therapy (a combination of individual and group sessions with therapists acting as behavior coaches and available on call around the clock)

  • Systems training for emotional predictability and problem solving (STEPPS)

STEPPS involves weekly group sessions for 20 weeks. Patients are taught skills to manage their emotions, to challenge their negative expectations, and to better care for themselves. They learn to set goals; avoid illegal substances; and improve their eating, sleeping, and exercise habits. Patients are asked to identify a support team of friends, family members, and health care practitioners who are willing to coach them when they are in crisis.

Other interventions focus on disturbances in the ways patients emotionally experience themselves and others. These interventions include the following:

  • Mentalization-based treatment

  • Transference-focused psychotherapy

  • Schema-focused therapy

Mentalization refers to people's ability to reflect on and understand their own state of mind and the state of mind of others. Mentalization is thought to be learned through a secure attachment to the caregiver. Mentalization-based treatment helps patients do the following:

  • Effectively regulate their emotions (eg, calm down when upset)

  • Understand how they contribute to their problems and difficulties with others

  • Reflect on and understand the minds of others

It thus helps them relate to others with empathy and compassion.

Transference-focused psychotherapy centers on the interaction between patient and therapist. The therapist asks questions and helps patients think about their reactions so that they can examine their exaggerated, distorted, and unrealistic images of self during the session. The current moment (eg, how patients are relating to their therapist) is emphasized rather than the past. For example, when a timid, quiet patient suddenly becomes hostile and argumentative, the therapist may ask whether the patient noticed a shift in feelings and then ask the patient to think about how the patient was experiencing the therapist and self when things changed. The purpose is

  • To enable patients to develop a more stable and realistic sense of self and others

  • To relate to others in a healthier way through transference to the therapist

Schema-focused therapy is an integrative therapy that combines cognitive-behavioral therapy, attachment theory, psychodynamic concepts, and emotion-focused therapies. It focuses on lifelong maladaptive patterns of thinking, feeling, behaving and coping (called schemas), affective change techniques, and the therapeutic relationship, with limited re-parenting. Limited re-parenting involves establishing a secure attachment between patient and therapist (within professional limits), enabling the therapist to help the patient experience what the patient missed during childhood that led to maladaptive behavior.

The purpose of schema-focused therapy is to help patients change their schemas. Therapy has 3 stages:

  • Assessment: Identifying the schemas

  • Awareness: Recognizing the schemas when they are operating in daily life

  • Behavioral change: Replacing negative thoughts, feelings, and behaviors with healthier ones

Some of these interventions are specialized and require specialized training and supervision. However, some interventions do not; one such intervention, which is designed for the general practitioner, is

  • General (or good) psychiatric management

Good psychiatric management includes individual therapy once a week, psychoeducation about borderline personality disorder and treatment goals and expectations, and sometimes drugs. It focuses on the patient’s reactions to interpersonal stressors in everyday life.

Supportive psychotherapy is also useful. The goal is to establish an emotional, encouraging, supportive relationship with the patient and thus help the patient develop healthy defense mechanisms, especially in interpersonal relationships.


Drugs work best when used sparingly and systematically for specific symptoms.

Selective serotonin reuptake inhibitors Selective Serotonin Reuptake Inhibitors (SSRIs) Several drug classes and drugs can be used to treat depression: Selective serotonin reuptake inhibitors (SSRIs) Serotonin modulators (5-HT2 blockers) Serotonin-norepinephrine reuptake inhibitors... read more (SSRIs) are usually well-tolerated; chance of a lethal overdose is minimal. However, SSRIs are only marginally effective for depression and anxiety in patients with borderline personality disorder.

The following drugs may be effective in ameliorating symptoms of borderline personality disorder:

More Information

The following is an English-language resource that may be useful. Please note that THE MANUAL is not responsible for the content of this resource.

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