Borderline personality disorder (BPD) is a mental illness. It develops during adolescence or early adulthood. It’s marked by a pattern of emotional instability, impulsive behavior, distorted self-image, and unstable relationships. According to the National Institute of Mental Health, about 1.6 percent of adults in the United States have BPD.

Researchers are still trying to learn the exact cause of BPD. Multiple factors may contribute to the disorder, including genetics, environmental factors, and serotonin abnormalities.


BPD may be a genetic condition. A study on twins and BPD published in the Journal of Personality Disorders suggests the disorder has a substantial genetic component.

Environmental factors

Growing up in an unstable, abusive, or neglectful environment may raise your risk of developing BPD.

Serotonin abnormalities

Serotonin is a hormone that helps regulate mood. Abnormalities in serotonin production may make you susceptible to BPD.

You may be at risk of developing BPD if:

  • you have a family member with BPD
  • you felt emotionally unstable or emotionally vulnerable as a child
  • people in your household were impulsive when you were a child
  • you were emotionally abused as a child

According to the American Psychiatric Association’s Diagnostic and Statistical Manual of Mental Disorders (DSM), the following criteria are all signs and symptoms of BPD.

  • You frantically try to avoid real or imaginary abandonment.
  • You have a pattern of unstable relationships. You alternate between idealizing and devaluing others in your relationships.
  • You have an unstable self-image or self-identity.
  • You act impulsively in at least two areas of your life in ways that can be self-damaging. For example, you may spend too much money or abuse substances.
  • You have a history of suicidal or self-mutilating behavior.
  • You have frequent mood swings. They usually last for a few hours but may last for a few days or more.
  • You have severe and long-term feelings of emptiness.
  • You have difficulty controlling your anger or you get severely angry without cause. You may feel angry all the time, display your anger frequently, or get in frequent physical fights.
  • You have periods of stress-related paranoia or experience severe dissociation. Dissociation occurs when you feel like your mind is detached from your emotions or body.

You must meet at least five of the official criteria from the DSM to be diagnosed with BPD.

If your doctor thinks you might have BPD, they will probably refer you to a mental health professional. They can make a diagnosis. They will ask you questions and analyze your emotional and behavioral history.

Your mental health professional may recommend one or more treatments for BPD, including psychotherapy, medication, or hospitalization.


Psychotherapy is the main treatment for BPD. Your mental health professional may recommend one of the following types: cognitive behavioral therapy (CBT), dialectical behavior therapy (DBT), and schema-focused therapy.

CBT helps you to identify and change unhealthy beliefs, behaviors, and inaccurate perceptions you may have about yourself or others. It teaches you healthy ways to react when you feel angry, insecure, anxious, or suicidal.

DBT teaches you how to recognize, be aware of, and accept your beliefs and behaviors. You also learn healthy responses to these behaviors .

Schema-focused therapy helps you to view yourself and the world in a more positive way.


Medication doesn’t cure BPD, but it can relieve symptoms. Your doctor may prescribe medication in addition to psychotherapy treatment. For example, they may prescribe:

  • antidepressants to treat depression
  • antipsychotics to treat aggressive symptoms
  • antianxiety medications to treat anxiety


If your symptoms are severe, your doctor may recommend that you temporarily stay in a hospital for treatment. You may also be hospitalized for suicidal behavior, suicidal thoughts, or thinking about harming yourself or others.

Alternative therapy

Omega-3 fatty acids may relieve symptoms of depression and aggression in people who have BPD. More research is needed to confirm the benefits of omega-3 fatty acids.

BPD may raise your risk of other disorders, such as:

  • depression
  • anxiety disorders
  • eating disorders
  • bipolar disorder
  • substance abuse

Your BPD symptoms can also increase your risk of:

  • work problems
  • relationship problems
  • being in an abusive relationship, as the abused or the abuser
  • sexually transmitted infections
  • self-injury
  • suicide
  • getting in a motor vehicle accident
  • getting in physical fights
  • becoming the victim of violent crimes

The outlook for people with BPD varies. You may face lifelong challenges associated with your BPD. At times, you may struggle with suicidal thoughts or self-harming behaviors. Following your doctor’s prescribed treatment plan is essential. It can reduce the severity of your symptoms and help you lead a safe and fulfilling life.