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Quick Facts

Borderline Personality Disorder


The Manual's Editorial Staff

Last full review/revision Oct 2020| Content last modified Oct 2020
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Your personality is your unique way of thinking, understanding, reacting, and relating to people.

A personality disorder isn't just an unusual personality. It's when your personality traits cause significant problems in your life or keep you from relating normally to others.

What is borderline personality disorder?

Borderline personality disorder is:

  • A pattern of wildly changing moods, relationships, and behavior

People with borderline personality disorder often:

  • Become panicky or angry when a friend is a few minutes late or cancels an appointment, which makes them feel abandoned

  • Have a quick temper and lash out verbally at friends, partners, and family, particularly when they think someone isn't meeting their high demands for support

  • Shift their views rapidly, such as going from praising someone to suddenly being overly critical

  • Impulsively do unwise things, such as having unsafe sex, overspending, driving recklessly, using drugs, or drinking too much

  • Sabotage themselves when about to reach a goal, such as dropping out of school right before graduation

  • Hurt themselves on purpose, such as by cutting or burning

  • Create crises, such as attempting suicide, to keep other people from abandoning them

Although most self-destructive things they do aren't fatal, almost 1 in 10 people with borderline personality die from suicide.

Even though they're needy, people with borderline personality disorder typically have unstable relationships. They may suddenly go from idolizing a friend to criticizing and dumping them.

Borderline personality disorder is more common in women than in men. People with borderline personality disorder may also have eating disorders, anxiety, depression, PTSD, or alcohol or drug abuse.

What causes borderline personality disorder?

Borderline personality disorder is probably caused by both:

  • Genes (the genetic information passed to you from your parents)—borderline personality disorder runs in families

  • Stresses during childhood, such as physical or sexual abuse, neglect, or being separated from a parent

How do doctors treat borderline personality disorder?

Doctors treat borderline personality disorder with:

  • Therapy (individual and group)

  • Medicine for mood and anxiety

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