What is borderline personality disorder?

Borderline personality disorder (BPD) is a serious mental illness. BPD is one of four personality disorders within Cluster B, the unpredictable and dramatic group of disorders. People with these disorders have intense, unstable emotions and a distorted self-image. People with BPD also display unpredictable and impulsive behavior, have unstable relationships, and suffer from identity confusion. BPD can be summarized as an inability to regulate emotions, especially with regard to relationships.

The instability often felt by people with this disorder can disrupt family and work life, and affect their self-identity. People with BPD are likely to have other mental health problems, as well, such as substance abuse, anxiety disorders, eating disorders and depression.

BPD is more common in women than in men. It usually surfaces in the teen years or early adulthood.

What causes borderline personality disorder?

The exact cause of BPD is not known, but most researchers believe that it is a combination of biological (body) and psychological (mind) factors. People with this disorder might be born with a vulnerability to the disorder, which is then triggered by stress or other factors.

For example, research suggests the following possible causes of BPD:

  • A malfunction in the brain might be responsible for the impulsiveness, mood instability, anger, and negative emotions.
  • Psychological "triggers" might include childhood trauma, such as abuse, neglect, prolonged separation, or inconsistent parenting.
  • A disruptive family life and poor communication within the family also are risk factors for the development of BPD.

What are the symptoms of borderline personality disorder?

People with BPD have extreme and long-term instability in their emotional lives, which affects their behavior and self-image. Symptoms that are common in people with BPD include the following:

  • Intense but chaotic personal relationships
  • Unpredictable, dangerous and/or impulsive behavior, such as excessive spending, risky sex, reckless driving, substance abuse, shoplifting, and binge eating, or physically self-destructive behavior, such as injuring themselves or suicide attempts
  • Rapid mood swings, and periods of intense depression, irritability, and anxiety (which might last only hours)
  • Intense or inappropriate anger
  • Confusion about self-image, sexual orientation, and choice of careers or friends
  • Frequent feelings of emptiness and boredom
  • Franticly avoiding abandonment (real or imagined)
  • Discomfort with being alone
  • Brief periods of confused thinking and perception during times of great stress
  • Extreme "black and white" views of people and experiences (They are either entirely good or entirely bad.)

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