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Borderline personality disorder

Read about borderline personality disorder. Personality disorders can cause a range of distressing symptoms and patterns of abnormal behaviour.

About this information

This NHS content is written for people in England. Services, entitlements and contact routes may differ in other countries.

Overview - Borderline personality disorder

Symptoms

Overview - Borderline personality disorder

Medical treatments

Overview - Borderline personality disorder

Causes

Symptoms of borderline personality include being emotionally unstable, having upsetting thoughts and acting without thinking.

The main treatment for borderline personality disorder is a type of talking therapy called psychotherapy.

The cause of borderline personality disorder is unclear. It's been linked to traumatic events during childhood, such as neglect or abuse.

Symptoms of borderline personality disorder (BPD)

The symptoms of BPD can be grouped into 4 main areas:

  • emotional instability – the psychological term for this is affective dysregulation
  • disturbed patterns of thinking or perception – cognitive distortions or perceptual distortions
  • impulsive behaviour
  • intense but unstable relationships with others

The symptoms of a personality disorder may range from mild to severe and usually emerge in adolescence, persisting into adulthood.

Causes of borderline personality disorder (BPD)

The causes of BPD are unclear. BPD appears to result from a combination of genetic and environmental factors.

People with BPD come from many different backgrounds, but most will have experienced some kind of trauma or neglect as children.

Treating borderline personality disorder (BPD)

Many people with BPD can benefit from psychological or medical treatment.

Treatment may involve a range of individual and group psychological therapies (psychotherapy) carried out by trained professionals working with a community mental health team (CMHT).

Effective treatment may last more than a year.

Over time, many people with BPD overcome their symptoms and recover. Additional treatment is recommended for people whose symptoms return.

Content supplied by the NHS website

Content supplied by the NHS website, refreshed 19 August 2026. View the original NHS article ↗

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