Borderline personality disorder (BPD)

BPD affects how a person feels about themselves, relates to others and manages emotions. People with BPD often experience emotions more intensely and for longer than others, and it can take time to return to a calm baseline.

The condition usually becomes noticeable in adolescence or early adulthood. It is diagnosed by a qualified mental health professional, such as a psychiatrist or clinical psychologist, after a careful assessment. An online BPD test may help you reflect, but it cannot provide a diagnosis.

BPD has historically been stigmatized and misunderstood. It is not a character flaw, and people with BPD are not manipulative by nature. Their behaviors usually reflect overwhelming emotional pain and attempts to cope with it. With understanding and the right treatment, people with BPD can build stable, meaningful lives.

BPD symptoms can vary from person to person. Common features include:

• Intense fear of abandonment and efforts to avoid real or imagined rejection.
• Unstable, intense relationships that swing between idealization and disappointment.
• An unstable sense of identity or self-image.
• Impulsive behaviors, such as overspending, risky sex, substance use or binge eating.
• Self-harm or suicidal thoughts and behaviors.
• Rapid mood changes lasting hours to a few days.
• Chronic feelings of emptiness.
• Intense anger or difficulty controlling anger.
• Stress-related paranoia or feeling disconnected from yourself or reality.

The "BPD favorite person" is an informal term for someone a person with BPD becomes intensely attached to and depends on for emotional stability. Their mood may rise and fall based on that relationship.

Quiet BPD is an informal term for people whose symptoms are mostly directed inward. Instead of showing anger outwardly, they may suppress emotions, blame themselves, withdraw, experience intense shame and self-harm in secret. Because they may appear calm, their distress is easily overlooked.

BPD can be confused with or occur alongside other conditions:

• Bipolar disorder: involves longer mood episodes of depression and mania or hypomania, while BPD mood shifts are usually shorter and tied to relationships or stress.
• Complex PTSD: shares emotional dysregulation and relationship difficulties, often linked to prolonged trauma.
• Depression, anxiety, eating disorders, ADHD and substance use disorders are also common alongside BPD.

A thorough assessment by a psychiatrist or clinical psychologist can clarify what is going on and guide treatment.

BPD likely develops from an interaction of factors:

• Biological sensitivity: some people are born with a more reactive emotional system, and BPD can run in families.
• Early environment: childhood trauma, abuse, neglect, loss or growing up in an environment where emotions were dismissed or punished.
• Brain differences: research suggests differences in areas involved in emotion regulation and impulse control.

Not everyone with BPD has experienced trauma, and not everyone who experiences trauma develops BPD. The biosocial model, which underpins dialectical behavior therapy, suggests that emotional sensitivity combined with an invalidating environment makes it hard to learn how to regulate emotions.

Understanding these roots can reduce shame and help people approach their difficulties with more compassion. It also helps explain why learning new skills, rather than simply trying harder, is at the heart of treatment.

BPD responds well to specialized psychotherapy. Effective approaches include:

• Dialectical behavior therapy (DBT): the most researched treatment for BPD. It teaches skills in mindfulness, distress tolerance, emotion regulation and interpersonal effectiveness, typically through individual therapy and skills groups.
• Mentalization-based treatment (MBT): helps people understand their own and others' thoughts and feelings.
• Schema therapy: addresses long-standing patterns rooted in childhood.
• Transference-focused psychotherapy: explores relationship patterns through the therapeutic relationship.

There is no medication specifically approved for BPD, but a psychiatrist may prescribe medication for related symptoms, such as depression, anxiety or severe mood swings.

A first session usually explores your history, current difficulties and safety. Many people find relief simply in having their experience understood. Over time, many people with BPD experience a significant reduction in symptoms.

People with BPD can experience overwhelming distress, self-harm urges or suicidal thoughts. If you or someone you know is in danger:

• Call 911 in the US or your local emergency number.
• Call or text 988 to reach the 988 Suicide & Crisis Lifeline in the US.
• Call Samaritans on 116 123 in the UK and Ireland.

It can help to create a crisis plan with your therapist, listing warning signs, coping skills, people to contact and professional services.

If you love someone with BPD, validate their feelings even when you don't agree with their actions, set clear and kind boundaries, and look after your own wellbeing. Family skills programs can help. Remember that a crisis is temporary, even when it feels endless, and that reaching out is a sign of strength.